UclibcApplication

CVE-2017-9729

HIGH · 7.5 CVSS v3.0 Published 2017-06-16
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

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
In uClibc 0.9.33.2, there is stack exhaustion (uncontrolled recursion) in the check_dst_limits_calc_pos_1 function in misc/regex/regexec.c when processing a crafted regular expression.

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 stack exhaustion vulnerability exists in uClibc 0.9.33.2's regex engine where the check_dst_limits_calc_pos_1 function in misc/regex/regexec.c suffers from uncontrolled recursion when processing specially crafted regular expressions. An attacker can trigger this to cause stack overflow and denial of service.

MitigationUpgrade to a patched version of uClibc if available; otherwise, implement regex input validation or complexity limits in applications using the affected regex functionality to prevent execution of deeply recursive patterns.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
UclibcApplication
Affected:= 0.9.33.2

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
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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 if the environment uses uClibc
    Check for the presence of uClibc library files (libc.so, libuclibc.so) or examine build/configuration files that reference uClibc as the C library. On embedded systems, inspect the filesystem for uClibc shared objects.
    Affected if The system or application is linked against uClibc as its C library implementation.
  2. Determine the installed uClibc version
    Run 'ldd --version' if available, or check the library file metadata. On embedded systems, examine the uClibc library file itself or the build configuration that specifies the uClibc version.
    Affected if The installed version is exactly 0.9.33.2.
  3. Verify if the regex engine is in use
    Search application code for inclusion of regex.h header and calls to regcomp(), regexec(), or regfree() functions. Inspect binary dependencies to confirm the regex component from uClibc is linked.
    Affected if Applications or binaries are using the regex functionality from the uClibc library.
  4. Determine if regex input is externally influenced
    Review application code paths that feed data into regcomp() calls. Identify whether untrusted or user-controlled strings are passed as the regex pattern argument.
    Affected if The regex pattern argument to regcomp() can be influenced by external input without sufficient validation.

The environment is affected if it uses uClibc version 0.9.33.2, links against its regex functionality, and processes external input through the regex engine.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to a patched version of uClibc if available; otherwise, implement regex input validation or complexity limits in applications using the affected regex functionality to prevent execution of deeply recursive patterns.

Fix this in Uclibc Scoped from the published advisory
  • Consultation3.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA3.0 h
20.0 hours of engineering $3,480
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,568.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2017-9729 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2017-9729 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data