glibc: De-recursivise regular expression engine
Published Jan 13, 2011
5.0
MEDIUMCVSS 2.0
EPSS 40.00%
Description
The regcomp implementation in the GNU C Library (aka glibc or libc6) through 2.11.3, and 2.12.x through 2.12.2, allows context-dependent attackers to cause a denial of service (application crash) via a regular expression containing adjacent bounded repetitions that bypass the intended RE_DUP_MAX limitation, as demonstrated by a {10,}{10,}{10,}{10,}{10,} sequence in the proftpd.gnu.c exploit for ProFTPD, related to a "RE_DUP_MAX overflow."
Affected products
No data.
- 1.00
- 1.01
- 1.02
- 1.03
- 1.04
- 1.05
- 1.06
- 1.07
- 1.08
- 1.09
- 1.09.1
- 2.1
- 2.1.1
- 2.1.1.6
- 2.1.2
- 2.1.3
- 2.1.3.10
- 2.1.9
- 2.10
- 2.10.1
- 2.10.2
- 2.11
- 2.11.1
- 2.11.2
- 2.11.3
- 2.12.0
- 2.12.1
- 2.12.2
No data.
Red Hat Enterprise Linux 4
glibc
Not affected
Red Hat Enterprise Linux 5
glibc
Not affected
Red Hat Enterprise Linux 6
glibc
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 4 | glibc | Not affected | n/a |
| Red Hat Enterprise Linux 5 | glibc | Not affected | n/a |
| Red Hat Enterprise Linux 6 | glibc | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Red Hat does not consider crash of client application, using regcomp() or regexec() routines on untrusted input without preliminary checking the input for the sanity, to be a security issue (the described deficiency implies and is a known limitation of the glibc regular expression engine implementation). The expressions can be modified to avoid quantification nesting, or program modified to limit size of input passed to regular expression engine. We do not currently plan to fix these flaws. If more information becomes available at a future date, we may revisit these issues.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (14 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 40.00% (0.39995) | 98.59th | v5 (v2026.06.15) |
| Jun 15, 2026 | 40.00% (0.39995) | 98.44th | v5 (v2026.06.15) |
| Mar 30, 2025 | 4.85% (0.04846) | 88.53th | v4 (v2025.03.14) |
| Mar 29, 2025 | 9.59% (0.09593) | 88.02th | v4 (v2025.03.14) |
| Mar 17, 2025 | 4.85% (0.04846) | 88.80th | v4 (v2025.03.14) |
| Dec 17, 2024 | 4.95% (0.04954) | 92.72th | v3 (v2023.03.01) |
| Nov 8, 2023 | 1.82% (0.01820) | 86.81th | v3 (v2023.03.01) |
| Jul 15, 2023 | 1.52% (0.01520) | 85.27th | v3 (v2023.03.01) |
| May 8, 2023 | 2.11% (0.02109) | 87.47th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.52% (0.01520) | 84.94th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.54% (0.01537) | 74.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.54% (0.01537) | 72.41th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
No CWE recorded.
References (15)
- http://cxib.net/stuff/proftpd.gnu.c x_refsource_MISCPatch
- http://seclists.org/fulldisclosure/2011/Jan/78 mailing-listx_refsource_FULLDISCExploit
- http://secunia.com/advisories/42547 third-party-advisoryx_refsource_SECUNIAVendor Advisory
- http://securityreason.com/achievement_securityalert/93 third-party-advisoryx_refsource_SREASONRESExploit
- http://securityreason.com/securityalert/8003 third-party-advisoryx_refsource_SREASONExploit
- http://securitytracker.com/id?1024832 vdb-entryx_refsource_SECTRACK
- http://www.exploit-db.com/exploits/15935 exploitx_refsource_EXPLOIT-DB
- http://www.kb.cert.org/vuls/id/912279 third-party-advisoryx_refsource_CERT-VNUS Government Resource
- http://www.securityfocus.com/archive/1/515589/100/0/threaded mailing-listx_refsource_BUGTRAQ
- http://www.securityfocus.com/bid/45233 vdb-entryx_refsource_BIDExploit
- https://access.redhat.com/security/cve/CVE-2010-4051 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=645859 x_refsource_MISCExploitIssue Tracking
- https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3E mailing-listx_refsource_MLIST
- https://nvd.nist.gov/vuln/detail/CVE-2010-4051
- https://www.cve.org/CVERecord?id=CVE-2010-4051
Change history (0)
No recorded changes yet.