CVE-2019-20454: An out-of-bounds read was discovered in PCRE before 10.34 when the pattern \X is JIT compiled and used to match specially crafted subjects i
Noroxi assessment
Priority: Monitor (action score 30/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 1.5% (FIRST EPSS); higher than 75.2% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: apcu-panel (AlmaLinux:8) 5.1.17-1.module_el8.3.0+2009+b272fdef; libzip (AlmaLinux:8) 1.5.2-1.module_el8.4.0+2229+b272fdef, 1.5.2-1.module_el8.5.0+152+112d3b8c, 1.5.2-1.module_el8.3.0+2009+b272fdef; libzip-devel (AlmaLinux:8) 1.5.2-1.module_el8.3.0+2009+b272fdef, 1.5.2-1.module_el8.5.0+152+112d3b8c, 1.5.2-1.module_el8.4.0+2229+b272fdef.
- Severity is disputed: the assigning authority (CNA) scores it 5.1, NVD 7.5.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to apcu-panel (AlmaLinux:8) 5.1.17-1.module_el8.3.0+2009+b272fdef; libzip (AlmaLinux:8) 1.5.2-1.module_el8.4.0+2229+b272fdef, 1.5.2-1.module_el8.5.0+152+112d3b8c, 1.5.2-1.module_el8.3.0+2009+b272fdef; libzip-devel (AlmaLinux:8) 1.5.2-1.module_el8.3.0+2009+b272fdef, 1.5.2-1.module_el8.5.0+152+112d3b8c, 1.5.2-1.module_el8.4.0+2229+b272fdef or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
An out-of-bounds read was discovered in PCRE before 10.34 when the pattern \X is JIT compiled and used to match specially crafted subjects in non-UTF mode. Applications that use PCRE to parse untrusted input may be vulnerable to this flaw, which would allow an attacker to crash the application. The flaw occurs in do_extuni_no_utf in pcre2_jit_compile.c.
- Published
- Feb 14, 2020
- Updated
- Nov 2, 2026
- EPSS
- 1.5% · 75th percentile
- CWE
- CWE-125
Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.5%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 7.5
- CNA · mitre
- 5.1
- 2.4 point gap
CVSS:3.0/AC:H/AV:L/A:H/C:N/I:N/PR:N/S:U/UI:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| pcre | pcre2 | cpe:2.3:a:pcre:pcre2 |
| fedoraproject | fedora | cpe:2.3:o:fedoraproject:fedora |
| splunk | universal forwarder | cpe:2.3:a:splunk:universal_forwarder |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- fedoraproject fedora31
- pcre pcre210.31 and later · before 10.34
- splunk universal forwarder8.2.0 and later · before 8.2.12
- splunk universal forwarder9.0.0 and later · before 9.0.6
- splunk universal forwarder9.1.0
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | apcu-panel | before 5.1.17-1.module_el8.3.0+2009+b272fdef | 5.1.17-1.module_el8.3.0+2009+b272fdef |
| AlmaLinux:8 | libzip | before 1.5.2-1.module_el8.4.0+2229+b272fdef | 1.5.2-1.module_el8.4.0+2229+b272fdef |
| AlmaLinux:8 | libzip | before 1.5.2-1.module_el8.5.0+152+112d3b8c | 1.5.2-1.module_el8.5.0+152+112d3b8c |
| AlmaLinux:8 | libzip | before 1.5.2-1.module_el8.3.0+2009+b272fdef | 1.5.2-1.module_el8.3.0+2009+b272fdef |
| AlmaLinux:8 | libzip-devel | before 1.5.2-1.module_el8.3.0+2009+b272fdef | 1.5.2-1.module_el8.3.0+2009+b272fdef |
| AlmaLinux:8 | libzip-devel | before 1.5.2-1.module_el8.5.0+152+112d3b8c | 1.5.2-1.module_el8.5.0+152+112d3b8c |
| AlmaLinux:8 | libzip-devel | before 1.5.2-1.module_el8.4.0+2229+b272fdef | 1.5.2-1.module_el8.4.0+2229+b272fdef |
| AlmaLinux:8 | libzip-tools | before 1.5.2-1.module_el8.5.0+152+112d3b8c | 1.5.2-1.module_el8.5.0+152+112d3b8c |
| AlmaLinux:8 | libzip-tools | before 1.5.2-1.module_el8.4.0+2229+b272fdef | 1.5.2-1.module_el8.4.0+2229+b272fdef |
| AlmaLinux:8 | libzip-tools | before 1.5.2-1.module_el8.3.0+2009+b272fdef | 1.5.2-1.module_el8.3.0+2009+b272fdef |
| AlmaLinux:8 | pcre2 | before 10.32-2.el8 | 10.32-2.el8 |
| AlmaLinux:8 | pcre2-devel | before 10.32-2.el8 | 10.32-2.el8 |
| AlmaLinux:8 | pcre2-tools | before 10.32-2.el8 | 10.32-2.el8 |
| AlmaLinux:8 | pcre2-utf16 | before 10.32-2.el8 | 10.32-2.el8 |
| AlmaLinux:8 | pcre2-utf32 | before 10.32-2.el8 | 10.32-2.el8 |
| AlmaLinux:8 | php | before 7.3.20-1.module_el8.4.0+2229+b272fdef | 7.3.20-1.module_el8.4.0+2229+b272fdef |
| AlmaLinux:8 | php | before 7.3.20-1.module_el8.5.0+152+112d3b8c | 7.3.20-1.module_el8.5.0+152+112d3b8c |
| AlmaLinux:8 | php | before 7.3.20-1.module_el8.3.0+2009+b272fdef | 7.3.20-1.module_el8.3.0+2009+b272fdef |
| AlmaLinux:8 | php-bcmath | before 7.3.20-1.module_el8.4.0+2229+b272fdef | 7.3.20-1.module_el8.4.0+2229+b272fdef |
| AlmaLinux:8 | php-bcmath | before 7.3.20-1.module_el8.5.0+152+112d3b8c | 7.3.20-1.module_el8.5.0+152+112d3b8c |
| AlmaLinux:8 | php-bcmath | before 7.3.20-1.module_el8.3.0+2009+b272fdef | 7.3.20-1.module_el8.3.0+2009+b272fdef |
| AlmaLinux:8 | php-cli | before 7.3.20-1.module_el8.5.0+152+112d3b8c | 7.3.20-1.module_el8.5.0+152+112d3b8c |
| AlmaLinux:8 | php-cli | before 7.3.20-1.module_el8.4.0+2229+b272fdef | 7.3.20-1.module_el8.4.0+2229+b272fdef |
| AlmaLinux:8 | php-cli | before 7.3.20-1.module_el8.3.0+2009+b272fdef | 7.3.20-1.module_el8.3.0+2009+b272fdef |
+96
Same product
pcre: all recordsOther highest-scoring records for the same primary product.
- CVE-2015-3210Heap-based buffer overflow in PCRE 8.34 through 8.37 and PCRE2 10.10 allows remote attackers to execute arbitrary code via a crafted regular42Plan
- CVE-2017-8786pcre2test.c in PCRE2 10.23 allows remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified ot40Plan
- CVE-2017-8399PCRE2 before 10.30 has an out-of-bounds write caused by a stack-based buffer overflow in pcre2_match.c, related to a "pattern with very many40Plan
Published before and after this one in the same product
- ← EarlierCVE-2015-3217Dec 13, 2016 · PCRE 7.8 and 8.32 through 8.37, and PCRE2 10.10 mishandle group empty matches, which might allow remote attackers to cause a denial of servi32Monitor
- Later →CVE-2022-1586May 16, 2022 · An out-of-bounds read vulnerability was discovered in the PCRE2 library in the compile_xclass_matchingpath() function of the pcre2_jit_compi37Monitor
- Later →CVE-2022-1587May 16, 2022 · An out-of-bounds read vulnerability was discovered in the PCRE2 library in the get_recurse_data_length() function of the pcre2_jit_compile.c37Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| almalinux:apcu-panel | 5.1.17-1.module_el8.3.0+2009+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| almalinux:libzip | 1.5.2-1.module_el8.5.0+152+112d3b8c · AlmaLinux:8 | Package registry (OSV) |
| almalinux:libzip-devel | 1.5.2-1.module_el8.4.0+2229+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| almalinux:libzip-tools | 1.5.2-1.module_el8.5.0+152+112d3b8c · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php | 7.3.20-1.module_el8.4.0+2229+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php-bcmath | 7.3.20-1.module_el8.4.0+2229+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php-cli | 7.3.20-1.module_el8.5.0+152+112d3b8c · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php-common | 7.3.20-1.module_el8.3.0+2009+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php-dba | 7.3.20-1.module_el8.5.0+152+112d3b8c · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php-dbg | 7.3.20-1.module_el8.3.0+2009+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php-devel | 7.3.20-1.module_el8.4.0+2229+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| almalinux:php-embedded | 7.3.20-1.module_el8.3.0+2009+b272fdef · AlmaLinux:8 | Package registry (OSV) |
| debian:pcre2 | 10.34-1 · Debian:12 | Package registry (OSV) |
| opensuse:pcre2 | 10.31-150000.3.12.1 · openSUSE:Leap 15.3 | Package registry (OSV) |
| red hat:apcu-panel | 0:5.1.17-1.module+el8.1.0+3189+a1bff096 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libzip | 0:1.5.2-1.module+el8.1.0+3189+a1bff096 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libzip-debuginfo | 0:1.5.2-1.module+el8.1.0+3189+a1bff096 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libzip-debugsource | 0:1.5.2-1.module+el8.1.0+3189+a1bff096 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libzip-devel | 0:1.5.2-1.module+el8.1.0+3189+a1bff096 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libzip-tools | 0:1.5.2-1.module+el8.1.0+3189+a1bff096 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libzip-tools-debuginfo | 0:1.5.2-1.module+el8.1.0+3189+a1bff096 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:php | 0:7.3.20-1.module+el8.2.0+7373+b272fdef · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:php-bcmath | 0:7.3.20-1.module+el8.2.0+7373+b272fdef · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:php-bcmath-debuginfo | 0:7.3.20-1.module+el8.2.0+7373+b272fdef · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:php-cli | 0:7.3.20-1.module+el8.2.0+7373+b272fdef · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:php-cli-debuginfo | 0:7.3.20-1.module+el8.2.0+7373+b272fdef · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| rocky linux:libzip | 0:1.5.2-1.module+el8.4.0+414+2e7afcdd · Rocky Linux:8 | Package registry (OSV) |
| rocky linux:pcre2 | 0:10.32-2.el8 · Rocky Linux:8 | Package registry (OSV) |
| rocky linux:php | 0:7.3.20-1.module+el8.4.0+414+2e7afcdd · Rocky Linux:8 | Package registry (OSV) |
| rocky linux:php-pear | 1:1.10.9-1.module+el8.4.0+414+2e7afcdd · Rocky Linux:8 | Package registry (OSV) |
+5
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-22-0552 · Aug 15, 2022(RedHat Güvenlik Güncellemesi)
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-125 · Out-of-bounds ReadCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (5 more)Show less
- bugzilla.redhat.com/show_bug.cgi?id=1735494
- lists.debian.org/debian-lts-announce/2023/03/msg00014.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OQRAHYHLRNMBTPR3KXVM27NSZP3KTOPI/
- security.gentoo.org/glsa/202006-16
- vcs.pcre.org/pcre2?view=revision&revision=1092
Vendor advisories and official records. Exploit/PoC links are deliberately left out.