pjproject: Out-of-bounds Read
CVE-2026-34235 is a critical-severity out-of-bounds read vulnerability in pjproject from Pjsip, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected pjproject versions: < 2.17. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.42% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Pjsip to 2.17 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 6.9 | Medium | CNA (github.com) |
| CVSS 3.1 | 9.1 | Critical | NVD |
| CVSS 3.1 | 9.1 | Critical | CISA (ADP) |
Official description
PJSIP is a free and open source multimedia communication library written in C. Prior to version 2.17, a heap out-of-bounds read vulnerability exists in PJSIP's VP9 RTP unpacketizer that occurs when parsing crafted VP9 Scalability Structure (SS) data. Insufficient bounds checking on the payload descriptor length may cause reads beyond the allocated RTP payload buffer. This issue has been patched in version 2.17. A workaround for this issue involves disabling VP9 codec if not needed.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in pjproject
- 7.4 High severity
- 7.1 High severity
- 9.1 Critical severity
- 9.1 Critical severity
- 8.2 High severity
- 7.5 High severity
Recent Out-of-bounds Read vulnerabilities
- 7.1 High severity
- 8.1 High severity
- 8.2 High severity
- 7.5 High severity
- 7.3 High severity
- 7.5 High severity
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