php: use-after-free vulnerability in session deserializer
Published May 16, 2016
9.8
CRITICALCVSS 3.0
EPSS 36.16%
Description
The session deserializer in PHP before 5.4.45, 5.5.x before 5.5.29, and 5.6.x before 5.6.13 mishandles multiple php_var_unserialize calls, which allow remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via crafted session content.
Affected products
No data.
Configuration 1
- 5.6.0
- 5.6.0
- 5.6.0
- 5.6.0
- 5.6.0
- 5.6.0
- 5.6.0
- 5.6.0
- 5.6.0
- 5.6.1
- 5.6.2
- 5.6.3
- 5.6.4
- 5.6.5
- 5.6.6
- 5.6.7
- 5.6.8
- 5.6.9
- 5.6.10
- 5.6.11
- 5.6.12
Configuration 3
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.0
- 5.5.1
- 5.5.2
- 5.5.3
- 5.5.4
- 5.5.5
- 5.5.6
- 5.5.7
- 5.5.8
- 5.5.9
- 5.5.10
- 5.5.11
- 5.5.12
- 5.5.13
- 5.5.14
- 5.5.15
- 5.5.16
- 5.5.17
- 5.5.18
- 5.5.19
- 5.5.20
- 5.5.21
- 5.5.22
- 5.5.23
- 5.5.24
- 5.5.25
- 5.5.26
- 5.5.27
- 5.5.28
No data.
Red Hat Software Collections for Red Hat Enterprise Linux 6
rh-php56-php-0:5.6.5-8.el6
Fixed · RHSA-2016:0457
Red Hat Software Collections for Red Hat Enterprise Linux 6.6 EUS
rh-php56-php-0:5.6.5-8.el6
Fixed · RHSA-2016:0457
Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS
rh-php56-php-0:5.6.5-8.el6
Fixed · RHSA-2016:0457
Red Hat Software Collections for Red Hat Enterprise Linux 7
rh-php56-php-0:5.6.5-8.el7
Fixed · RHSA-2016:0457
Red Hat Software Collections for Red Hat Enterprise Linux 7.1 EUS
rh-php56-php-0:5.6.5-8.el7
Fixed · RHSA-2016:0457
Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS
rh-php56-php-0:5.6.5-8.el7
Fixed · RHSA-2016:0457
Red Hat Enterprise Linux 5
php
Will not fix
Red Hat Enterprise Linux 5
php53
Will not fix
Red Hat Enterprise Linux 6
php
Will not fix
Red Hat Enterprise Linux 7
php
Will not fix
Red Hat Software Collections
php54-php
Will not fix
Red Hat Software Collections
php55-php
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | rh-php56-php-0:5.6.5-8.el6 | Fixed | RHSA-2016:0457 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6.6 EUS | rh-php56-php-0:5.6.5-8.el6 | Fixed | RHSA-2016:0457 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS | rh-php56-php-0:5.6.5-8.el6 | Fixed | RHSA-2016:0457 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | rh-php56-php-0:5.6.5-8.el7 | Fixed | RHSA-2016:0457 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.1 EUS | rh-php56-php-0:5.6.5-8.el7 | Fixed | RHSA-2016:0457 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS | rh-php56-php-0:5.6.5-8.el7 | Fixed | RHSA-2016:0457 |
| Red Hat Enterprise Linux 5 | php | Will not fix | n/a |
| Red Hat Enterprise Linux 5 | php53 | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | php | Will not fix | n/a |
| Red Hat Enterprise Linux 7 | php | Will not fix | n/a |
| Red Hat Software Collections | php54-php | Will not fix | n/a |
| Red Hat Software Collections | php55-php | Will not fix | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
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:H/I:H/A:H
AV:N/AC:L/Au:N/C:P/I:P/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 (46 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 36.16% (0.36163) | 98.43th | v5 (v2026.06.15) |
| Sep 22, 2026 | 36.99% (0.36992) | 98.45th | v5 (v2026.06.15) |
| Sep 21, 2026 | 31.90% (0.31903) | 98.27th | v5 (v2026.06.15) |
| Sep 6, 2026 | 36.99% (0.36992) | 98.41th | v5 (v2026.06.15) |
| Sep 5, 2026 | 31.90% (0.31903) | 98.23th | v5 (v2026.06.15) |
| Aug 30, 2026 | 36.99% (0.36992) | 98.40th | v5 (v2026.06.15) |
| Aug 28, 2026 | 31.90% (0.31903) | 98.22th | v5 (v2026.06.15) |
| Aug 24, 2026 | 36.99% (0.36992) | 98.40th | v5 (v2026.06.15) |
| Aug 23, 2026 | 31.90% (0.31903) | 98.21th | v5 (v2026.06.15) |
| Jun 15, 2026 | 36.99% (0.36992) | 98.31th | v5 (v2026.06.15) |
| May 9, 2026 | 22.60% (0.22600) | 95.89th | v4 (v2025.03.14) |
| Dec 28, 2025 | 21.30% (0.21302) | 95.50th | v4 (v2025.03.14) |
| Dec 27, 2025 | 25.90% (0.25898) | 96.11th | v4 (v2025.03.14) |
| Nov 4, 2025 | 21.30% (0.21302) | 95.45th | v4 (v2025.03.14) |
| Oct 28, 2025 | 20.13% (0.20127) | 95.24th | v4 (v2025.03.14) |
| Oct 27, 2025 | 24.57% (0.24566) | 95.88th | v4 (v2025.03.14) |
| Oct 1, 2025 | 19.52% (0.19519) | 95.23th | v4 (v2025.03.14) |
| Jul 30, 2025 | 24.57% (0.24566) | 95.89th | v4 (v2025.03.14) |
| Jun 16, 2025 | 20.13% (0.20127) | 95.17th | v4 (v2025.03.14) |
| Jun 5, 2025 | 22.00% (0.22000) | 95.45th | v4 (v2025.03.14) |
| Jun 1, 2025 | 19.60% (0.19600) | 95.13th | v4 (v2025.03.14) |
| May 6, 2025 | 22.00% (0.22000) | 95.41th | v4 (v2025.03.14) |
| May 1, 2025 | 19.60% (0.19600) | 95.09th | v4 (v2025.03.14) |
| Apr 19, 2025 | 22.00% (0.22000) | 95.39th | v4 (v2025.03.14) |
| Apr 18, 2025 | 19.60% (0.19600) | 95.03th | v4 (v2025.03.14) |
| Apr 17, 2025 | 22.00% (0.22000) | 95.38th | v4 (v2025.03.14) |
| Apr 16, 2025 | 19.60% (0.19600) | 95.02th | v4 (v2025.03.14) |
| Apr 12, 2025 | 22.00% (0.22000) | 95.31th | v4 (v2025.03.14) |
| Apr 7, 2025 | 39.37% (0.39370) | 97.01th | v4 (v2025.03.14) |
| Apr 6, 2025 | 36.12% (0.36123) | 96.79th | v4 (v2025.03.14) |
| Mar 30, 2025 | 39.37% (0.39370) | 97.00th | v4 (v2025.03.14) |
| Mar 29, 2025 | 62.65% (0.62654) | 97.69th | v4 (v2025.03.14) |
| Mar 28, 2025 | 39.37% (0.39370) | 97.00th | v4 (v2025.03.14) |
| Mar 27, 2025 | 62.65% (0.62654) | 98.14th | v4 (v2025.03.14) |
| Mar 20, 2025 | 45.78% (0.45784) | 97.38th | v4 (v2025.03.14) |
| Mar 19, 2025 | 62.65% (0.62654) | 98.18th | v4 (v2025.03.14) |
| Mar 18, 2025 | 42.46% (0.42458) | 97.18th | v4 (v2025.03.14) |
| Mar 17, 2025 | 45.78% (0.45784) | 97.33th | v4 (v2025.03.14) |
| Dec 12, 2024 | 9.01% (0.09007) | 94.88th | v3 (v2023.03.01) |
| Jun 15, 2024 | 9.01% (0.09007) | 94.63th | v3 (v2023.03.01) |
| Nov 29, 2023 | 8.82% (0.08823) | 93.93th | v3 (v2023.03.01) |
| Nov 8, 2023 | 8.88% (0.08882) | 93.92th | v3 (v2023.03.01) |
| Oct 27, 2023 | 5.70% (0.05698) | 92.47th | v3 (v2023.03.01) |
| Mar 7, 2023 | 5.12% (0.05118) | 91.69th | v3 (v2023.03.01) |
| Mar 6, 2023 | 46.67% (0.46675) | 98.43th | v2 (v2022.01.01) |
| Feb 4, 2022 | 46.67% (0.46675) | 97.92th | v2 (v2022.01.01) |
References (10)
- http://php.net/ChangeLog-5.php x_refsource_CONFIRM
- http://www.debian.org/security/2015/dsa-3358 vendor-advisoryx_refsource_DEBIAN
- http://www.securityfocus.com/bid/76734 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1033548 vdb-entryx_refsource_SECTRACK
- https://access.redhat.com/security/cve/CVE-2015-6835 Vendor Advisory
- https://bugs.php.net/bug.php?id=70219 x_refsource_CONFIRM
- https://bugzilla.redhat.com/show_bug.cgi?id=1260647 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2015-6835
- https://security.gentoo.org/glsa/201606-10 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2015-6835
| Link | Providers | Tags |
|---|---|---|
| http://php.net/ChangeLog-5.php | x_refsource_CONFIRM | |
| http://www.debian.org/security/2015/dsa-3358 | vendor-advisoryx_refsource_DEBIAN | |
| http://www.securityfocus.com/bid/76734 | vdb-entryx_refsource_BID | |
| http://www.securitytracker.com/id/1033548 | vdb-entryx_refsource_SECTRACK | |
| https://access.redhat.com/security/cve/CVE-2015-6835 | Vendor Advisory | |
| https://bugs.php.net/bug.php?id=70219 | x_refsource_CONFIRM | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1260647 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2015-6835 | ||
| https://security.gentoo.org/glsa/201606-10 | vendor-advisoryx_refsource_GENTOO | |
| https://www.cve.org/CVERecord?id=CVE-2015-6835 |
Change history (0)
No recorded changes yet.