pjproject: Improper Validation of Array Index
CVE-2026-57159 is a high-severity improper validation of array index vulnerability in pjproject from Pjsip, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected pjproject versions: < 673b978aab1fe3ab874247be32c871acc880cbeb. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.6% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of pjproject you run against the affected versions below, and install the vendor's latest release.
- 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
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Pjsip | pjproject | < 673b978aab1fe3ab874247be32c871acc880cbeb | Not stated |
| Teluu | Pjsip | 2.17 and earlier | Not stated |
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
- NoneNo data is disclosed.
- 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:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.4 | High | CNA (github.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
PJSIP is a free and open source multimedia communication library written in C. Prior to commit 673b978, a remote out-of-bounds read and write can occur in the SDP negotiator when the remote payload-type map maintenance feature is enabled. assign_pt_and_update_map() in pjmedia/src/pjmedia/sdp_neg.c uses payload-type numbers taken from a remote SDP offer or answer to index fixed-size internal tables without sufficient bounds validation, so a crafted remote SDP can cause memory access outside those tables. The practical impact is memory corruption and denial of service; code execution is not demonstrated. This path is only reached when PJMEDIA_SDP_NEG_MAINTAIN_REMOTE_PT_MAP is enabled. The default is disabled, so default builds are not affected; the feature is an interoperability option that integrating products may enable. This issue has been patched via commit 673b978.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Validation of Array Index
The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array.
How developers prevent this class of flaw
- Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, Ada allows the programmer to constrain the values of a variable and languages such as Java and Ruby will allow the programmer to handle exceptions when an out-of-bounds index is accessed.
- Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment. For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND.
More Improper Validation of Array Index vulnerabilities (CWE-129)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- 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 Improper Validation of Array Index vulnerabilities
- 8.8 High severity
- 8.7 High severity
- 7.5 High severity
- 7.0 High severity
- 7.8 High severity
- 7.8 High severity
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