CVE-2026-56109
CVE-2026-56109 is a medium-severity vulnerability with a CVSS 3.x base score of 6.8. 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-415.
Key facts
- Severity: Medium (CVSS 3.x base score 6.8)
- CVSS v4: 7.0
- EPSS exploit prediction: 0% (4th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-38301
- Weakness: CWE-415
- Published:
- Last modified:
Description
The Advanced Linux Sound Architecture (ALSA) library before 1.2.16.1 contains a double-free vulnerability in parse_def() in src/conf.c that allows attackers to corrupt memory by supplying maliciously crafted ALSA configuration text. When parsing nested compound or array configuration blocks, parse_def() fails to check return values before continuing, causing snd_config_delete() to be called twice on the same already-freed node, resulting in a NULL-pointer write or invalid memory read.
Frequently asked questions
- What is CVE-2026-56109?
- The Advanced Linux Sound Architecture (ALSA) library before 1.2.16.1 contains a double-free vulnerability in parse_def() in src/conf.c that allows attackers to corrupt memory by supplying maliciously crafted ALSA configuration text. When parsing nested compound or array configuration blocks, parse_def() fails to check return values before continuing, causing snd_config_delete() to be called twice on the same already-freed node, resulting in a NULL-pointer write or invalid memory read.
- How severe is CVE-2026-56109?
- CVE-2026-56109 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
- Is CVE-2026-56109 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-56109?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-56109 have an EU (EUVD) identifier?
- Yes. CVE-2026-56109 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38301.
- When was CVE-2026-56109 published?
- CVE-2026-56109 was published on 2026-06-22 and last updated on 2026-06-23.
References
- https://github.com/alsa-project/alsa-lib/commit/536dd6f8affdf5197c12a63a71c92a70b2833cc0
- https://github.com/alsa-project/alsa-lib/releases/tag/v1.2.16.1
- https://lore.kernel.org/alsa-devel/CAGt8pqBU0p2voB+qHxWGcNJrKHAcBhAyHUUBPLBN-Yj_SiV6MQ@mail.gmail.com/
- https://www.vulncheck.com/advisories/alsa-library-double-free-via-parse-def-in-conf-c
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