Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2012-3949 — cisco / ios

Improper Input Validation

The SIP implementation in Cisco Unified Communications Manager (CUCM) 6.x and 7.x before 7.1(5b)su5, 8.x before 8.5(1)su4, and 8.6 before 8.6(2a)su1; Cisco IOS 12.2 through 12.4 and 15.0 through 15.2; and Cisco IOS XE 3.3.xSG before 3.3.1SG, 3.4.xS, and 3.5.xS allows remote attackers to cause a denial of service (service crash or device reload) via a crafted SIP message containing an SDP session description, aka Bug IDs CSCtw66721, CSCtj33003, and CSCtw84664.

  • Published: Sep 27, 2012
  • Updated: Nov 9, 2025
  • CVE: CVE-2012-3949
  • Severity: High
  • Exploit:

CVSS v2:

  • Severity: High
  • Score: 7.8
  • AV:N/AC:L/Au:N/C:N/I:N/A:C

CWEs:

Software From Fixed in
cisco / ios 12.2xnd 12.2xnd.x
cisco / ios 12.3ym 12.3ym.x
cisco / ios 12.3yq 12.3yq.x
cisco / ios 12.3xr 12.3xr.x
cisco / unified_communications_manager 6.1(3a) 6.1(3a).x
cisco / ios 12.2sga 12.2sga.x
cisco / ios 12.3bc 12.3bc.x
cisco / unified_communications_manager 8.0(2c) 8.0(2c).x
cisco / ios 12.2xr 12.2xr.x
cisco / ios 12.3ya 12.3ya.x
cisco / unified_communications_manager 6.1(2) 6.1(2).x
cisco / ios_xe 3.5.0s 3.5.0s.x
cisco / ios 12.2cz 12.2cz.x
cisco / ios 12.2sxf 12.2sxf.x
cisco / ios 12.2fy 12.2fy.x
cisco / ios_xe 3.4.1s 3.4.1s.x
cisco / ios 15.1 15.1.x
cisco / ios 12.2xe 12.2xe.x
cisco / ios 12.2scb 12.2scb.x
cisco / ios 12.3xs 12.3xs.x
cisco / ios 12.2sx 12.2sx.x
cisco / ios 12.3xg 12.3xg.x
cisco / ios_xe 3.3.1s 3.3.1s.x
cisco / ios 12.2zp 12.2zp.x
cisco / ios 12.3bw 12.3bw.x
cisco / ios 12.3xd 12.3xd.x
cisco / ios 12.2ca 12.2ca.x
cisco / ios 12.2bz 12.2bz.x
cisco / ios 12.2ys 12.2ys.x
cisco / ios 12.3xw 12.3xw.x
cisco / ios 12.2xj 12.2xj.x
cisco / ios 12.2srb 12.2srb.x
cisco / ios 12.2su 12.2su.x
cisco / ios 12.2xh 12.2xh.x
cisco / unified_communications_manager 8.0(2) 8.0(2).x
cisco / ios 12.2xg 12.2xg.x
cisco / ios 12.2ew 12.2ew.x
cisco / ios 12.2b 12.2b.x
cisco / ios 12.2ixb 12.2ixb.x
cisco / ios 12.2svc 12.2svc.x
cisco / ios 15.0 15.0.x
cisco / ios 12.2sea 12.2sea.x
cisco / ios 12.3xi 12.3xi.x
cisco / ios 15.1xb 15.1xb.x
cisco / ios 12.2yn 12.2yn.x
cisco / unified_communications_manager 7.1(2b) 7.1(2b).x
cisco / unified_communications_manager 8.5(1)su2 8.5(1)su2.x
cisco / ios_xe 3.3.1sg 3.3.1sg.x
cisco / ios 12.2sxa 12.2sxa.x
cisco / ios 12.2ey 12.2ey.x
cisco / ios 12.2zx 12.2zx.x
cisco / ios 12.2seg 12.2seg.x
cisco / ios 12.3yj 12.3yj.x
cisco / unified_communications_manager 7.1(5b)su4 7.1(5b)su4.x
cisco / ios 12.2xb 12.2xb.x
cisco / ios 12.2yf 12.2yf.x
cisco / ios 12.2sg 12.2sg.x
cisco / ios 12.2ixf 12.2ixf.x
cisco / ios_xe 3.5.2s 3.5.2s.x
cisco / ios 12.3jec 12.3jec.x
cisco / unified_communications_manager 7.1(3b) 7.1(3b).x
cisco / unified_communications_manager 8.0(2b) 8.0(2b).x
cisco / ios 12.2xl 12.2xl.x
cisco / ios 15.0mra 15.0mra.x
cisco / unified_communications_manager 6.1(4) 6.1(4).x
cisco / ios 12.2ym 12.2ym.x
cisco / ios 12.2yw 12.2yw.x
cisco / ios 12.3yu 12.3yu.x
cisco / ios 12.2yd 12.2yd.x
cisco / ios 12.3t 12.3t.x
cisco / ios 12.2yb 12.2yb.x
cisco / ios 12.3 12.3.x
cisco / ios 12.2mb 12.2mb.x
cisco / ios 15.1t 15.1t.x
cisco / ios 12.2dd 12.2dd.x
cisco / ios 12.2zh 12.2zh.x
cisco / ios 12.2da 12.2da.x
cisco / ios 12.2zu 12.2zu.x
cisco / ios 12.2yv 12.2yv.x
cisco / ios 12.2ixa 12.2ixa.x
cisco / ios 12.2sxb 12.2sxb.x
cisco / ios_xe 3.4.0as 3.4.0as.x
cisco / ios 12.2yo 12.2yo.x
cisco / ios 12.2xw 12.2xw.x
cisco / ios 12.2sca 12.2sca.x
cisco / unified_communications_manager 7.1(5b)su1 7.1(5b)su1.x
cisco / ios 12.3va 12.3va.x
cisco / ios 12.2t 12.2t.x
cisco / ios 12.2zc 12.2zc.x
cisco / ios 12.2sv 12.2sv.x
cisco / unified_communications_manager 6.1(4a) 6.1(4a).x
cisco / unified_communications_manager 7.1(5b)su3 7.1(5b)su3.x
cisco / ios 12.2seb 12.2seb.x
cisco / ios 15.0sg 15.0sg.x
cisco / ios 12.3xz 12.3xz.x
cisco / ios 12.2yt 12.2yt.x
cisco / ios 12.2zya 12.2zya.x
cisco / ios 12.2yl 12.2yl.x
cisco / ios 12.2sed 12.2sed.x
cisco / ios 15.0s 15.0s.x
cisco / ios 12.2za 12.2za.x
cisco / ios 15.1gc 15.1gc.x
cisco / ios 12.2xn 12.2xn.x
cisco / ios 12.2ye 12.2ye.x
cisco / ios 15.0m 15.0m.x
cisco / ios 12.2ez 12.2ez.x
cisco / ios 12.3yd 12.3yd.x
cisco / ios 12.2sr 12.2sr.x
cisco / ios 15.0(1)s2 15.0(1)s2.x
cisco / ios 12.2zb 12.2zb.x
cisco / unified_communications_manager 6.1(3) 6.1(3).x
cisco / ios 12.2yg 12.2yg.x
cisco / unified_communications_manager 7.1(3) 7.1(3).x
cisco / ios 12.2sva 12.2sva.x
cisco / ios 12.2ex 12.2ex.x
cisco / ios 12.2svd 12.2svd.x
cisco / ios 12.2xu 12.2xu.x
cisco / ios 15.1s 15.1s.x
cisco / unified_communications_manager 7.1(2) 7.1(2).x
cisco / ios 12.2sbc 12.2sbc.x
cisco / ios 12.2ixc 12.2ixc.x
cisco / ios 12.3xf 12.3xf.x
cisco / ios 12.3xl 12.3xl.x
cisco / unified_communications_manager 7.1(2a) 7.1(2a).x
cisco / ios 12.2yr 12.2yr.x
cisco / ios 12.2se 12.2se.x
cisco / ios 15.0sa 15.0sa.x
cisco / unified_communications_manager 6.1(1) 6.1(1).x
cisco / ios 12.3yk 12.3yk.x
cisco / ios_xe 3.4.3s 3.4.3s.x
cisco / unified_communications_manager 7.1(5b) 7.1(5b).x
cisco / ios 12.3yf 12.3yf.x
cisco / ios 12.2sec 12.2sec.x
cisco / ios 15.0mr 15.0mr.x
cisco / unified_communications_manager 8.0 8.0.x
cisco / ios 12.2sb 12.2sb.x
cisco / ios_xe 3.5.xs 3.5.xs.x
cisco / ios 12.2xm 12.2xm.x
cisco / unified_communications_manager 8.5(1)su3 8.5(1)su3.x
cisco / ios 12.3yt 12.3yt.x
cisco / ios 12.2sy 12.2sy.x
cisco / ios 12.2xk 12.2xk.x
cisco / ios 12.3xb 12.3xb.x
cisco / ios 12.2ixg 12.2ixg.x
cisco / ios 12.2zj 12.2zj.x
cisco / ios 12.3yz 12.3yz.x
cisco / ios 12.2zy 12.2zy.x
cisco / ios 12.3jl 12.3jl.x
cisco / ios 12.3yg 12.3yg.x
cisco / ios 12.3xu 12.3xu.x
cisco / ios 12.2zd 12.2zd.x
cisco / ios 12.3xy 12.3xy.x
cisco / ios_xe 3.4.0s 3.4.0s.x
cisco / unified_communications_manager 7.1(5b)su2 7.1(5b)su2.x
cisco / ios 12.2cy 12.2cy.x
cisco / ios 12.3xc 12.3xc.x
cisco / unified_communications_manager 7.1(5) 7.1(5).x
cisco / ios 12.2tpc 12.2tpc.x
cisco / ios 12.2xc 12.2xc.x
cisco / ios 12.2ewa 12.2ewa.x
cisco / ios 12.2bc 12.2bc.x
cisco / ios 12.3xe 12.3xe.x
cisco / unified_communications_manager 7.1(5a) 7.1(5a).x
cisco / ios 12.2yc 12.2yc.x
cisco / ios 12.3jea 12.3jea.x
cisco / ios 12.2ze 12.2ze.x
cisco / ios 15.0(1)se 15.0(1)se.x
cisco / ios 15.1(3)t 15.1(3)t.x
cisco / ios 15.1(4)m1 15.1(4)m1.x
cisco / ios 12.3tpc 12.3tpc.x
cisco / ios 12.3ja 12.3ja.x
cisco / ios 12.2xnb 12.2xnb.x
cisco / ios 12.2xs 12.2xs.x
cisco / ios 12.2yp 12.2yp.x
cisco / unified_communications_manager 6.1(1b) 6.1(1b).x
cisco / ios 12.2bw 12.2bw.x
cisco / ios 12.2yy 12.2yy.x
cisco / ios 12.2fx 12.2fx.x
cisco / ios 12.2sz 12.2sz.x
cisco / unified_communications_manager 6.1(3b) 6.1(3b).x
cisco / ios 12.2xi 12.2xi.x
cisco / ios_xe 3.4.2s 3.4.2s.x
cisco / ios 15.0(1)s1 15.0(1)s1.x
cisco / ios 12.3za 12.3za.x
cisco / ios 12.2yu 12.2yu.x
cisco / unified_communications_manager 6.1(5) 6.1(5).x
cisco / unified_communications_manager 7.1(1) 7.1(1).x
cisco / unified_communications_manager 6.1(4b) 6.1(4b).x
cisco / ios 15.1ey 15.1ey.x
cisco / ios 12.2sxi 12.2sxi.x
cisco / ios_xe 3.4.xs 3.4.xs.x
cisco / ios 15.1(2)t 15.1(2)t.x
cisco / ios 12.2l 12.2l.x
cisco / ios 12.3yx 12.3yx.x
cisco / unified_communications_manager 8.0(3) 8.0(3).x
cisco / ios 12.2dx 12.2dx.x
cisco / unified_communications_manager 7.1(5b)su1a 7.1(5b)su1a.x
cisco / unified_communications_manager 8.0(2a) 8.0(2a).x
cisco / ios 12.2ixd 12.2ixd.x
cisco / unified_communications_manager 6.0(1a) 6.0(1a).x
cisco / ios 12.2xd 12.2xd.x
cisco / ios 12.2bx 12.2bx.x
cisco / ios 12.3xq 12.3xq.x
cisco / ios 12.2cx 12.2cx.x
cisco / unified_communications_manager 6.0(1b) 6.0(1b).x
cisco / ios 12.2zl 12.2zl.x
cisco / ios 12.2yq 12.2yq.x
cisco / unified_communications_manager 8.0(3a) 8.0(3a).x
cisco / ios 12.2xf 12.2xf.x
cisco / ios 12.2xq 12.2xq.x
cisco / ios 12.2sef 12.2sef.x
cisco / ios 12.2rc 12.2rc.x
cisco / ios 15.1(1)xb1 15.1(1)xb1.x
cisco / ios 12.2see 12.2see.x
cisco / ios 12.3ys 12.3ys.x
cisco / ios 12.3jk 12.3jk.x
cisco / ios 12.2zf 12.2zf.x
cisco / ios 12.3b 12.3b.x
cisco / ios 12.2sra 12.2sra.x
cisco / ios 12.2irb 12.2irb.x
cisco / ios 12.3jeb 12.3jeb.x
cisco / unified_communications_manager 7.1(3a) 7.1(3a).x
cisco / ios 12.2sm 12.2sm.x
cisco / ios 12.3yh 12.3yh.x
cisco / ios 12.2ya 12.2ya.x
cisco / ios 12.2xv 12.2xv.x
cisco / ios 12.2 12.2.x
cisco / ios 12.2zg 12.2zg.x
cisco / ios 12.3xx 12.3xx.x
cisco / ios 12.2xnc 12.2xnc.x
cisco / ios 12.2sw 12.2sw.x
cisco / ios 15.1(4)m 15.1(4)m.x
cisco / ios 15.0xa 15.0xa.x
cisco / ios 12.3xa 12.3xa.x
cisco / ios 12.2yk 12.2yk.x
cisco / ios 12.2sxd 12.2sxd.x
cisco / ios 12.2src 12.2src.x
cisco / ios 15.0xo 15.0xo.x
cisco / ios 12.2yz 12.2yz.x
cisco / ios_xe 3.5.1s 3.5.1s.x
cisco / ios 12.2xa 12.2xa.x
cisco / ios 15.2 15.2.x
cisco / ios 12.2ixe 12.2ixe.x
cisco / unified_communications_manager 6.1(1a) 6.1(1a).x
cisco / unified_communications_manager 8.5(1)su1 8.5(1)su1.x
cisco / ios 12.3xk 12.3xk.x
cisco / ios 12.2yj 12.2yj.x
cisco / ios 12.2sve 12.2sve.x
cisco / ios_xe 3.3.0sg 3.3.0sg.x
cisco / ios 12.2yx 12.2yx.x
cisco / ios 12.2xo 12.2xo.x
cisco / ios 12.2sxe 12.2sxe.x
cisco / ios 12.3jx 12.3jx.x
cisco / unified_communications_manager 8.0(1) 8.0(1).x
cisco / ios 12.2by 12.2by.x
cisco / ios 12.2yh 12.2yh.x
cisco / ios 12.2s 12.2s.x
cisco / ios 12.2fz 12.2fz.x
cisco / ios 15.1m 15.1m.x
cisco / ios 12.2xt 12.2xt.x

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.