The malloc implementation in the GNU C Library (aka glibc or libc6), from version 2.24 to…
Priority MEDIUM 46CWE-190Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA. Impact type from CWE-190 and the CVSS impact.
Summary
The malloc implementation in the GNU C Library (aka glibc or libc6), from version 2.24 to 2.26 on powerpc, and only in version 2.26 on i386, did not properly handle malloc calls with arguments close to SIZE_MAX and could return a pointer to a heap region that is smaller than requested, eventually leading to heap corruption.
Why it matters now
EPSS 0.02208 82nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
Not affected: 4 products
- Red Hat Enterprise Linux 5
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2018-6551
- 2026-10-03 Alias added: GHSA-39wv-6252-46w2
References
More GNU Glibc vulnerabilities
- TI-2023-04522 Glibc: buffer overflow in ld.so leading to privilege escalation KEVCVSS 3.1HIGH 7.8
- TI-2015-00205 Heap-based buffer overflow in the __nss_hostname_digits_dots function in glibc 2.2, and… CVSS 2.0HIGH 10.0
- TI-2026-04772 scanf %mc off-by-one heap buffer overflow CVSS 3.1CRITICAL 9.8
- TI-2022-07360 The deprecated compatibility function clnt_create in the sunrpc module of the GNU C… CVSS 3.1CRITICAL 9.8
- TI-2022-07359 The deprecated compatibility function svcunix_create in the sunrpc module of the GNU C… CVSS 3.1CRITICAL 9.8
- TI-2015-06274 Multiple stack-based buffer overflows in the (1) send_dg and (2) send_vc functions in the… CVSS 3.0HIGH 8.1
Sources
- CVE-2018-6551 · CVE Program
- CVE-2018-6551 · NVD
- FIRST EPSS
- GHSA-39wv-6252-46w2 · GitHub Advisory Database · CC BY 4.0
- CVE-2018-6551 · Red Hat security data · CC BY 4.0
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