PatchTheCVECVE-2016-2851: Integer overflow in proto.c in libotr before 4.1.1 on 64-bit platforms allows remote attackers to cause a deni
CVE-2016-2851 is a critical-severity flaw (CVSS 9.8) affecting debian linux, leap, opensuse. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Integer overflow in proto.c in libotr before 4.1.1 on 64-bit platforms allows remote attackers to cause a denial of service (memory corruption and application crash) or execute arbitrary code via a series of large OTR messages, which triggers a heap-based buffer overflow.
Why this priority
- Critical severity
- EPSS top 2%: very likely to be exploited
- Public exploit reference
- Remotely exploitable, no login, no user action
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 24.3% (top 2%) |
| CISA exploited list | No |
| Weakness | CWE-119 |
| Published | 2016-04-07 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- Exploit-DB: libotr 4.1.0 - Memory Corruption
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2016-2851?
debian linux: mitigate or apply the listed mitigation; leap: mitigate or apply the listed mitigation; opensuse: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2016-2851 being exploited?
CVE-2016-2851 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2016-2851 affect?
CVE-2016-2851 affects debian linux, leap, opensuse. Severity is critical (CVSS 9.8). Integer overflow in proto.c in libotr before 4.1.1 on 64-bit platforms allows remote attackers to cause a denial of service (memory corruption and application crash) or execute arbitrary code via a series of large OTR messages, which trigge
How urgent is CVE-2016-2851?
Priority 74/100. Critical severity; EPSS top 2%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action; On your watchlist
Software pages
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