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Fencer Vulns
medium 4.3

CVE-2026-6103 json

Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection

published 2026-09-24 45 d ago modified 2026-10-26 13 d ago also BIT-libphp-2026-6103 , BIT-php-2026-6103 , BIT-php-min-2026-6103 , EUVD-2026-87322 , GHSA-j3wh-g957-2m85

cvss
4.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

phar_tar_number() parses the octal size field of a TAR header into a uint32_t with no overflow check. The field is 11 octal digits wide and holds values up to 0x1FFFFFFFF, so a size above 0xFFFFFFFF silently wraps. The parser then skips the wrong number of data blocks and interprets attacker-controlled file content as the next TAR header, which lets a crafted archive inject entries that PharData reports and extracts as if they were genuine.

Patch / fix

  • bitnami libphp 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • bitnami php 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • bitnami php-min 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • PHP Group PHP 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • php8.2 Debian 12 8.2.34-1~deb12u1
  • php8.4 Debian 13 8.4.26-1~deb13u1
  • php8.4 Debian 14 8.4.26-1

debian advisories DEBIAN-CVE-2026-6103

  • php8.1 Ubuntu 22.04 LTS 8.1.2-1ubuntu2.27
  • php8.3 Ubuntu 24.04 LTS 8.3.6-0ubuntu0.24.04.12
  • php8.5 Ubuntu 26.10 8.5.9-0ubuntu2
  • php8.5 Ubuntu 26.04 LTS 8.5.4-0ubuntu1.4
  • php5 Ubuntu Pro 14.04 LTS 5.5.9+dfsg-1ubuntu4.29+esm17
  • php7.0 Ubuntu Pro 16.04 LTS 7.0.33-0ubuntu0.16.04.16+esm21
  • php7.2 Ubuntu Pro 18.04 LTS 7.2.24-0ubuntu0.18.04.17+esm13
  • php7.4 Ubuntu Pro 20.04 LTS 7.4.3-4ubuntu2.29+esm4

ubuntu advisories UBUNTU-CVE-2026-6103

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • php hummingbird 1 8.5.11-2.hum1
  • php-gd hummingbird 1 8.5.11-2.hum1
  • php-cli hummingbird 1 8.5.11-2.hum1
  • php-dba hummingbird 1 8.5.11-2.hum1
  • php-dbg hummingbird 1 8.5.11-2.hum1
  • php-ffi hummingbird 1 8.5.11-2.hum1
  • php-fpm hummingbird 1 8.5.11-2.hum1
  • php-gmp hummingbird 1 8.5.11-2.hum1

red hat advisories RHSA-2026:70720

  • php7 SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +7 more 7.4.33-150400.4.81.1
  • php7-fpm SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +6 more 7.4.33-150400.4.81.1
  • php7-test SLE Module for Package Hub 15 SP7 7.4.33-150400.4.81.2
  • php7-embed SLE Module for Package Hub 15 SP7 7.4.33-150400.4.81.1
  • php7-fastcgi SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +6 more 7.4.33-150400.4.81.1
  • apache2-mod_php7 SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +7 more 7.4.33-150400.4.81.1
  • php8 SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 8.0.30-150400.4.76.1
  • php8-fpm SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 8.0.30-150400.4.76.1

suse advisories SUSE-SU-2026:4853-1SUSE-SU-2026:4651-1SUSE-SU-2026:4603-1SUSE-SU-2026:4602-1SUSE-SU-2026:24158-1

  • php8 openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-fpm openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-test openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-embed openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-fastcgi openSUSE Leap 16.0 8.4.26-160000.1.1
  • apache2-mod_php8 openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8 openSUSE Tumbleweed 8.5.11-1.1

opensuse advisories openSUSE-SU-2026:22045-1openSUSE-SU-2026:11901-1

  • php AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • libzip AlmaLinux 8 1.6.1-1.module_el8.6.0+2750+78feabcb
  • libzip AlmaLinux 8 1.6.1-1.module_el8.6.0+3239+bedf0508
  • libzip AlmaLinux 8 1.6.1-1.module_el8.10.0+3935+28808425
  • php-gd AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • php-cli AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • php-dba AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • php-dbg AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb

almalinux advisories ALSA-2026:87080

  • php Rocky Linux 8 7.4.33-8.module+el8.10.0+40393+c071e357
  • libzip Rocky Linux 8 1.6.1-1.module+el8.10.0+1912+72767185
  • libzip Rocky Linux 8 1.6.1-1.module+el8.10.0+1604+6558efc7
  • php-pear Rocky Linux 8 1:1.10.13-1.module+el8.10.0+1912+72767185
  • php-pear Rocky Linux 8 1:1.10.13-1.module+el8.10.0+1605+02e07af7
  • php-pear Rocky Linux 8 1:1.10.13-1.module+el8.10.0+1604+6558efc7
  • php-pecl-rrd Rocky Linux 8 2.0.1-1.module+el8.10.0+1604+6558efc7
  • php-pecl-rrd Rocky Linux 8 2.0.1-1.module+el8.10.0+1912+72767185

rocky linux advisories RLSA-2026:87080

  • php82 Alpine 3.22 8.2.35-r0
  • php83 Alpine 3.23, Alpine 3.22 8.3.36-r0
  • php83 Alpine 3.24 8.3.35-r0
  • php84 Alpine 3.23, Alpine 3.22 8.4.27-r0
  • php84 Alpine 3.24 8.4.26-r0
  • php85 Alpine 3.23 8.5.12-r0
  • php85 Alpine 3.24 8.5.11-r0

alpine advisories ALPINE-CVE-2026-6103

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-6103 updated cvss 4.3

php: PHP: Archive entry injection via integer overflow in TAR parser

  • Red Hat Enterprise Linux 6 php, php-gd, php-cli, php-dba, php-fpm, php-pdo, +21 more
    affected: workaround, no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 7 php, php-gd, php-cli, php-dba, php-fpm, php-pdo, +19 more Red Hat Enterprise Linux 8 php, libzip, php-gd, php-cli, php-dba, php-dbg, +30 more Red Hat Enterprise Linux 9 php, php-gd, php-cli, php-dba, php-dbg, php-ffi, +19 more Red Hat Enterprise Linux 10 php 8.3.33-1.el10_2, php8.4 8.4.24-2.el10
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Enterprise Linux AppStream (v. 8) php 7.4.33-8.module+el8.10.0+25117+30337cca, libzip 1.6.1-1.module+el8.10.0+22485+a3539972, php-gd 7.4.33-8.module+el8.10.0+25117+30337cca, php-cli 7.4.33-8.module+el8.10.0+25117+30337cca, php-dba 7.4.33-8.module+el8.10.0+25117+30337cca, php-dbg 7.4.33-8.module+el8.10.0+25117+30337cca, +28 more
    fixed: vendor fix RHSA-2026:87080
  • Red Hat Hardened Images php 8.5.11-2.hum1, php-gd 8.5.11-2.hum1, php-cli 8.5.11-2.hum1, php-dba 8.5.11-2.hum1, php-dbg 8.5.11-2.hum1, php-ffi 8.5.11-2.hum1, +21 more
    fixed: vendor fix RHSA-2026:70720

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
44 d ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/php/php-src/security/advisories/GHSA-j3wh-g957-2m85 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 4.3 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
NVD 3.1 3.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
OSV 3.1 4.3 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Affected packages

ecosystem package affected fixed in
bitnami libphp
>=8.2.0, <8.2.34
>=8.3.0, <8.3.35
>=8.4.0, <8.4.26
>=8.5.0, <8.5.11
8.2.34
8.3.35
8.4.26
8.5.11
bitnami php
>=8.2.0, <8.2.34
>=8.3.0, <8.3.35
>=8.4.0, <8.4.26
>=8.5.0, <8.5.11
8.2.34
8.3.35
8.4.26
8.5.11
bitnami php-min
>=8.2.0, <8.2.34
>=8.3.0, <8.3.35
>=8.4.0, <8.4.26
>=8.5.0, <8.5.11
8.2.34
8.3.35
8.4.26
8.5.11

Affected products

  • PHP Group PHP

Classification

Weakness
  • CWE-190 Integer Overflow or Wraparound
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of php/php-src published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.