perl: Heap buffer overflow in regular expression compiler
Published Sep 19, 2017
7.5
HIGHCVSS 3.0
EPSS 6.21%
Description
Heap-based buffer overflow in the S_regatom function in regcomp.c in Perl 5 before 5.24.3-RC1 and 5.26.x before 5.26.1-RC1 allows remote attackers to cause a denial of service (out-of-bounds write) via a regular expression with a '\N{}' escape and the case-insensitive modifier.
Affected products
No data.
No data.
Red Hat Hardened Images
perl-main-1.03-524.hum1
Fixed · RHSA-2026:6206
Red Hat Enterprise Linux 5
perl
Not affected
Red Hat Enterprise Linux 6
perl
Not affected
Red Hat Enterprise Linux 7
perl
Not affected
Red Hat Software Collections
rh-perl520-perl
Will not fix
Red Hat Software Collections
rh-perl524-perl
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Hardened Images | perl-main-1.03-524.hum1 | Fixed | RHSA-2026:6206 |
| Red Hat Enterprise Linux 5 | perl | Not affected | n/a |
| Red Hat Enterprise Linux 6 | perl | Not affected | n/a |
| Red Hat Enterprise Linux 7 | perl | Not affected | n/a |
| Red Hat Software Collections | rh-perl520-perl | Will not fix | n/a |
| Red Hat Software Collections | rh-perl524-perl | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue does not affect perl versions older than 5.18. Perl as shipped in Red Hat Enterprise Linux 7 and older are not affected by this 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:H/PR:N/UI:N/S:U/C:N/I:N/A:H
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 (25 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 6.21% (0.06207) | 93.30th | v5 (v2026.06.15) |
| Jun 15, 2026 | 6.21% (0.06207) | 92.59th | v5 (v2026.06.15) |
| Dec 28, 2025 | 2.58% (0.02585) | 85.15th | v4 (v2025.03.14) |
| Dec 27, 2025 | 4.28% (0.04284) | 88.53th | v4 (v2025.03.14) |
| Dec 11, 2025 | 2.58% (0.02585) | 85.11th | v4 (v2025.03.14) |
| Nov 23, 2025 | 3.60% (0.03601) | 87.28th | v4 (v2025.03.14) |
| Oct 28, 2025 | 2.58% (0.02585) | 85.02th | v4 (v2025.03.14) |
| Oct 27, 2025 | 4.28% (0.04284) | 88.36th | v4 (v2025.03.14) |
| Oct 1, 2025 | 2.58% (0.02585) | 85.10th | v4 (v2025.03.14) |
| Jul 30, 2025 | 4.28% (0.04284) | 88.39th | v4 (v2025.03.14) |
| Mar 30, 2025 | 2.07% (0.02065) | 82.32th | v4 (v2025.03.14) |
| Mar 29, 2025 | 5.13% (0.05127) | 82.70th | v4 (v2025.03.14) |
| Mar 17, 2025 | 2.07% (0.02065) | 82.72th | v4 (v2025.03.14) |
| Jul 20, 2024 | 2.07% (0.02072) | 89.21th | v3 (v2023.03.01) |
| Jul 10, 2024 | 2.07% (0.02072) | 89.17th | v3 (v2023.03.01) |
| Dec 24, 2023 | 1.85% (0.01855) | 87.02th | v3 (v2023.03.01) |
| Mar 22, 2023 | 1.83% (0.01830) | 86.36th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.90% (0.01903) | 86.67th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.97% (0.01974) | 78.97th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.97% (0.01974) | 77.12th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.97% (0.01974) | 56.20th | v2 (v2022.01.01) |
| Feb 3, 2022 | 3.21% (0.03209) | 66.48th | v1 |
| Jan 6, 2022 | 3.21% (0.03209) | 66.16th | v1 |
| Sep 1, 2021 | 3.21% (0.03209) | 81.46th | v1 |
| Apr 14, 2021 | 3.21% (0.03209) | 0.00th | v1 |
References (12)
- http://www.debian.org/security/2017/dsa-3982 vendor-advisoryx_refsource_DEBIAN
- http://www.securityfocus.com/bid/100860 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2017-12837 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1492091 x_refsource_CONFIRMIssue TrackingPatchThird Party AdvisoryVDB Entry
- https://nvd.nist.gov/vuln/detail/CVE-2017-12837
- https://perl5.git.perl.org/perl.git/commitdiff/96c83ed78aeea1a0496dd2b2d935869a822dc8a5 x_refsource_CONFIRMPatchVendor Advisory
- https://perl5.git.perl.org/perl.git/log/refs/tags/v5.24.3-RC1 x_refsource_CONFIRMRelease NotesVendor Advisory
- https://perl5.git.perl.org/perl.git/log/refs/tags/v5.26.1-RC1 x_refsource_CONFIRMRelease NotesVendor Advisory
- https://rt.perl.org/Public/Bug/Display.html?id=131582 x_refsource_CONFIRM
- https://security.netapp.com/advisory/ntap-20180426-0001/ x_refsource_CONFIRM
- https://www.cve.org/CVERecord?id=CVE-2017-12837
- https://www.oracle.com/security-alerts/cpujul2020.html x_refsource_MISC
Change history (0)
No recorded changes yet.