CVE-2020-6096
CVE-2020-6096 is a high-severity vulnerability in Gnu Glibc with a CVSS 3.x base score of 8.1. 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-195.
Key facts
- Severity: High (CVSS 3.x base score 8.1)
- CVSS v2: 6.8
- EPSS exploit prediction: 5% (92nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-195
- Affected product: Gnu Glibc
- Published:
- Last modified:
Description
An exploitable signed comparison vulnerability exists in the ARMv7 memcpy() implementation of GNU glibc 2.30.9000. Calling memcpy() (on ARMv7 targets that utilize the GNU glibc implementation) with a negative value for the 'num' parameter results in a signed comparison vulnerability. If an attacker underflows the 'num' parameter to memcpy(), this vulnerability could lead to undefined behavior such as writing to out-of-bounds memory and potentially remote code execution. Furthermore, this memcpy() implementation allows for program execution to continue in scenarios where a segmentation fault or crash should have occurred. The dangers occur in that subsequent execution and iterations of this code will be executed with this corrupted data.
Frequently asked questions
- What is CVE-2020-6096?
- An exploitable signed comparison vulnerability exists in the ARMv7 memcpy() implementation of GNU glibc 2.30.9000. Calling memcpy() (on ARMv7 targets that utilize the GNU glibc implementation) with a negative value for the 'num' parameter results in a signed comparison vulnerability. If an attacker underflows the 'num' parameter to memcpy(), this vulnerability could lead to undefined behavior such as writing to out-of-bounds memory and potentially remote code execution. Furthermore, this memcpy() implementation allows for program execution to continue in scenarios where a segmentation fault or crash should have occurred. The dangers occur in that subsequent execution and iterations of this code will be executed with this corrupted data.
- How severe is CVE-2020-6096?
- CVE-2020-6096 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-6096 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-6096?
- CVE-2020-6096 primarily affects Gnu Glibc. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-6096?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-6096 published?
- CVE-2020-6096 was published on 2020-04-01 and last updated on 2026-06-17.
References
- https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPYXTDOOB4PQGTYAMZAZNJIB3FF6YQXI/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/URXOIA2LDUKHQXK4BE55BQBRI6ZZG3Y6/
- https://security.gentoo.org/glsa/202101-20
- https://sourceware.org/bugzilla/show_bug.cgi?id=25620
- https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1019
Affected products (4)
- cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
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