How severe is CVE-2026-26203?

CVE-2026-26203 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-26203 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-26203?

CVE-2026-26203 affects Pjsip. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-26203?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-26203 have an EU (EUVD) identifier?

Yes. CVE-2026-26203 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7974.

When was CVE-2026-26203 published?

CVE-2026-26203 was published on 2026-02-19 and last updated on 2026-06-17.

CVE-2026-26203

CVE-2026-26203 is a medium-severity vulnerability in Pjsip with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 5.1
EPSS exploit prediction: 0% (1st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-7974
Weakness: CWE-416
Affected product: Pjsip
Published: 2026-02-19
Last modified: 2026-06-17

Description

PJSIP is a free and open source multimedia communication library. Versions prior to 2.17 have a critical heap buffer underflow vulnerability in PJSIP's H.264 packetizer. The bug occurs when processing malformed H.264 bitstreams without NAL unit start codes, where the packetizer performs unchecked pointer arithmetic that can read from memory located before the allocated buffer. Version 2.17 contains a patch for the issue.

Frequently asked questions

What is CVE-2026-26203?: PJSIP is a free and open source multimedia communication library. Versions prior to 2.17 have a critical heap buffer underflow vulnerability in PJSIP's H.264 packetizer. The bug occurs when processing malformed H.264 bitstreams without NAL unit start codes, where the packetizer performs unchecked pointer arithmetic that can read from memory located before the allocated buffer. Version 2.17 contains a patch for the issue.
How severe is CVE-2026-26203?: CVE-2026-26203 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-26203 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-26203?: CVE-2026-26203 affects Pjsip. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-26203?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-26203 have an EU (EUVD) identifier?: Yes. CVE-2026-26203 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7974.
When was CVE-2026-26203 published?: CVE-2026-26203 was published on 2026-02-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:pjsip:pjsip:*:*:*:*:*:*:*:*

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