glibc: uncontrolled recursion in function check_dst_limits_calc_pos_1 in posix/regexec.c
Published Feb 26, 2019
7.5
HIGHCVSS 3.0
EPSS 5.76%
Description
In the GNU C Library (aka glibc or libc6) through 2.29, check_dst_limits_calc_pos_1 in posix/regexec.c has Uncontrolled Recursion, as demonstrated by '(\227|)(\\1\\1|t1|\\\2537)+' in grep.
Affected products
No data.
Configuration 2
- n/a
- n/a
- n/a
No data.
Red Hat Enterprise Linux 6
glibc
Not affected
Red Hat Enterprise Linux 7
glibc
Not affected
Red Hat Enterprise Linux 8
glibc
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | glibc | Not affected | n/a |
| Red Hat Enterprise Linux 7 | glibc | Not affected | n/a |
| Red Hat Enterprise Linux 8 | glibc | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
The regular expression compiler in glibc is only supposed to be exposed to trusted content, therefore this flaw is not classified as a security vulnerability.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
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
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (26 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 5.76% (0.05757) | 92.84th | v5 (v2026.06.15) |
| Jun 15, 2026 | 5.80% (0.05804) | 92.13th | v5 (v2026.06.15) |
| Nov 21, 2025 | 1.79% (0.01786) | 82.15th | v4 (v2025.03.14) |
| Nov 18, 2025 | 10.42% (0.10424) | 92.46th | v4 (v2025.03.14) |
| Sep 18, 2025 | 2.16% (0.02158) | 83.66th | v4 (v2025.03.14) |
| Sep 16, 2025 | 4.50% (0.04496) | 88.68th | v4 (v2025.03.14) |
| Aug 15, 2025 | 2.41% (0.02410) | 84.45th | v4 (v2025.03.14) |
| Aug 12, 2025 | 5.00% (0.05003) | 89.28th | v4 (v2025.03.14) |
| Mar 30, 2025 | 1.79% (0.01786) | 81.09th | v4 (v2025.03.14) |
| Mar 29, 2025 | 21.82% (0.21815) | 93.08th | v4 (v2025.03.14) |
| Jul 20, 2024 | 0.44% (0.00440) | 75.09th | v3 (v2023.03.01) |
| Jul 19, 2024 | 0.44% (0.00440) | 75.09th | v3 (v2023.03.01) |
| Mar 26, 2024 | 0.63% (0.00630) | 78.56th | v3 (v2023.03.01) |
| Mar 9, 2024 | 0.44% (0.00444) | 74.36th | v3 (v2023.03.01) |
| Feb 20, 2024 | 0.62% (0.00624) | 78.30th | v3 (v2023.03.01) |
| Sep 21, 2023 | 0.68% (0.00678) | 77.53th | v3 (v2023.03.01) |
| Jul 24, 2023 | 0.48% (0.00478) | 72.57th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.50% (0.00503) | 72.75th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.02% (0.01018) | 40.69th | v2 (v2022.01.01) |
| Sep 10, 2022 | 1.02% (0.01018) | 38.88th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.02% (0.01018) | 36.86th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.02% (0.01018) | 19.50th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.25% (0.01247) | 30.57th | v1 |
| Jan 6, 2022 | 1.25% (0.01247) | 29.93th | v1 |
| Sep 1, 2021 | 1.25% (0.01247) | 68.62th | v1 |
| Apr 14, 2021 | 1.25% (0.01247) | 0.00th | v1 |
References (9)
- http://www.securityfocus.com/bid/107160 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2018-20796 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1683150 Issue Tracking
- https://debbugs.gnu.org/cgi/bugreport.cgi?bug=34141 x_refsource_MISCExploitMailing ListVendor Advisory
- https://lists.gnu.org/archive/html/bug-gnulib/2019-01/msg00108.html x_refsource_MISCExploitMailing ListVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2018-20796
- https://security.netapp.com/advisory/ntap-20190315-0002/ x_refsource_CONFIRMPatchThird Party Advisory
- https://support.f5.com/csp/article/K26346590?utm_source=f5support&%3Butm_medium=RSS x_refsource_CONFIRM
- https://www.cve.org/CVERecord?id=CVE-2018-20796
| Link | Providers | Tags |
|---|---|---|
| http://www.securityfocus.com/bid/107160 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| https://access.redhat.com/security/cve/CVE-2018-20796 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1683150 | Issue Tracking | |
| https://debbugs.gnu.org/cgi/bugreport.cgi?bug=34141 | x_refsource_MISCExploitMailing ListVendor Advisory | |
| https://lists.gnu.org/archive/html/bug-gnulib/2019-01/msg00108.html | x_refsource_MISCExploitMailing ListVendor Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2018-20796 | ||
| https://security.netapp.com/advisory/ntap-20190315-0002/ | x_refsource_CONFIRMPatchThird Party Advisory | |
| https://support.f5.com/csp/article/K26346590?utm_source=f5support&%3Butm_medium=RSS | x_refsource_CONFIRM | |
| https://www.cve.org/CVERecord?id=CVE-2018-20796 |
Change history (0)
No recorded changes yet.