CVE-2020-37239
CVE-2020-37239 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
- CVSS v4: 9.3
- EPSS exploit prediction: 0% (37th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2020-31239
- Weakness: CWE-415
- Published:
- Last modified:
Description
libbabl 0.1.62 contains a broken double free detection vulnerability that allows attackers to bypass memory safety checks by exploiting signature overwriting in freed chunks. Attackers can call babl_free() twice on the same pointer without triggering detection, as libc's malloc metadata overwrites babl's signature field upon freeing, enabling potential memory corruption and code execution.
Frequently asked questions
- What is CVE-2020-37239?
- libbabl 0.1.62 contains a broken double free detection vulnerability that allows attackers to bypass memory safety checks by exploiting signature overwriting in freed chunks. Attackers can call babl_free() twice on the same pointer without triggering detection, as libc's malloc metadata overwrites babl's signature field upon freeing, enabling potential memory corruption and code execution.
- How severe is CVE-2020-37239?
- CVE-2020-37239 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-37239 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2020-37239?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- Does CVE-2020-37239 have an EU (EUVD) identifier?
- Yes. CVE-2020-37239 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-31239.
- When was CVE-2020-37239 published?
- CVE-2020-37239 was published on 2026-05-16 and last updated on 2026-06-17.
References
- https://www.exploit-db.com/exploits/49259
- https://www.gegl.org
- https://www.gegl.org/babl/
- https://www.vulncheck.com/advisories/libbabl-broken-double-free-detection-memory-safety
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