Double FreeWeakness · CWE-415

CVE-2025-8058

MEDIUM · 5.9 CVSS v4.0 Published 2025-07-23
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
59/100
Remediation priority · Elevated

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The regcomp function in the GNU C library version from 2.4 to 2.41 is subject to a double free if some previous allocation fails. It can be accomplished either by a malloc failure or by using an interposed malloc that injects random malloc failures. The double free can allow buffer manipulation depending of how the regex is constructed. This issue affects all architectures and ABIs supported by the GNU C library.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A double-free vulnerability exists in glibc's regcomp function (regex compilation) in versions 2.4 through 2.41. When an allocation fails during regex compilation (either due to natural malloc failure or an interposed malloc), a subsequent double-free can occur, potentially allowing buffer manipulation. This affects all architectures and ABIs supported by the GNU C Library.

MitigationUpgrade glibc to a version newer than 2.41 when a patch is available. Until then, validate and sanitize regex patterns from untrusted sources before compilation, and avoid using untrusted or complex regex patterns in production environments.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
High
Privileges
Low
Authentication
X
User interaction
P
Scope
X

CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:H/SC:L/SI:L/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed glibc version
    Run 'ldd --version' or 'glibc --version' to determine the glibc version installed on the system
    Affected if The version shown is between 2.4 and 2.41 inclusive (e.g., 2.31, 2.35, 2.40)
  2. Confirm regcomp usage in deployed applications
    Search application binaries and scripts for calls to regcomp, regexec, regfree, or other regex compilation functions from <regex.h>
    Affected if Applications or services link against glibc and perform regex compilation via regcomp
  3. Identify code paths processing untrusted regex input
    Review application source code or binary behavior to determine if regex patterns originate from user input, network sources, configuration files, or external data
    Affected if The application compiles regex patterns derived from untrusted or remote sources without validation
  4. Check for interposed malloc implementations
    Review whether the application or its dependencies ship with custom malloc implementations that could alter allocation failure behavior during regex compilation
    Affected if A custom malloc is in use that may trigger allocation failures during regcomp execution

The environment is affected if glibc version is between 2.4 and 2.41 AND the system runs applications that compile regex patterns from untrusted sources using regcomp, which could trigger the double-free upon allocation failure.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade glibc to a version newer than 2.41 when a patch is available. Until then, validate and sanitize regex patterns from untrusted sources before compilation, and avoid using untrusted or complex regex patterns in production environments.

Recommended fix High confidence

glibc 2.42 or later

  1. 1. Check current glibc version using: ldd --version or /lib/x86_64-linux-gnu/libc.so.6
  2. 2. Obtain glibc version 2.42 or later from the official GNU C library source (https://ftp.gnu.org/gnu/glibc/)
  3. 3. Compile and install the new glibc version following standard build procedures (configure, make, make install)
  4. 4. Ensure all dependent applications are recompiled against the new library if necessary
  5. 5. Verify the installed version matches the expected fixed release
Caveat Major glibc upgrades may introduce ABI changes; test critical applications thoroughly before production deployment

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA8.0 h
44.0 hours of engineering $7,720
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Scan for this in your stack

Free · runs locally
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-8058 in production — separate from our analysis above.

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What this is

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