php: bcpowmod accepts negative scale causing heap buffer overflow corrupting _one_ definition
Published May 22, 2016
9.8
CRITICALCVSS 3.0
EPSS 6.06%
Description
The bcpowmod function in ext/bcmath/bcmath.c in PHP before 5.5.35, 5.6.x before 5.6.21, and 7.x before 7.0.6 modifies certain data structures without considering whether they are copies of the _zero_, _one_, or _two_ global variable, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via a crafted call.
Affected products
No data.
Configuration 1
- ≤ 5.5.33
- 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
- 5.6.13
- 5.6.14
- 5.6.15
- 5.6.16
- 5.6.17
- 5.6.18
- 5.6.19
- 5.6.20
- 7.0.0
- 7.0.1
- 7.0.2
- 7.0.3
- 7.0.4
- 7.0.5
Configuration 2
- 24
No data.
Red Hat Software Collections for Red Hat Enterprise Linux 6
rh-php56-0:2.3-1.el6
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 6
rh-php56-php-0:5.6.25-1.el6
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 6
rh-php56-php-pear-1:1.9.5-4.el6
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS
rh-php56-0:2.3-1.el6
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS
rh-php56-php-0:5.6.25-1.el6
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS
rh-php56-php-pear-1:1.9.5-4.el6
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7
rh-php56-0:2.3-1.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7
rh-php56-php-0:5.6.25-1.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7
rh-php56-php-pear-1:1.9.5-4.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS
rh-php56-0:2.3-1.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS
rh-php56-php-0:5.6.25-1.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS
rh-php56-php-pear-1:1.9.5-4.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS
rh-php56-0:2.3-1.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS
rh-php56-php-0:5.6.25-1.el7
Fixed · RHSA-2016:2750
Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS
rh-php56-php-pear-1:1.9.5-4.el7
Fixed · RHSA-2016:2750
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-php56-0:2.3-1.el6 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | rh-php56-php-0:5.6.25-1.el6 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | rh-php56-php-pear-1:1.9.5-4.el6 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS | rh-php56-0:2.3-1.el6 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS | rh-php56-php-0:5.6.25-1.el6 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS | rh-php56-php-pear-1:1.9.5-4.el6 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | rh-php56-0:2.3-1.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | rh-php56-php-0:5.6.25-1.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | rh-php56-php-pear-1:1.9.5-4.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS | rh-php56-0:2.3-1.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS | rh-php56-php-0:5.6.25-1.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS | rh-php56-php-pear-1:1.9.5-4.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS | rh-php56-0:2.3-1.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS | rh-php56-php-0:5.6.25-1.el7 | Fixed | RHSA-2016:2750 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS | rh-php56-php-pear-1:1.9.5-4.el7 | Fixed | RHSA-2016:2750 |
| 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 (21 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 6.06% (0.06063) | 93.17th | v5 (v2026.06.15) |
| Jun 15, 2026 | 6.23% (0.06229) | 92.61th | v5 (v2026.06.15) |
| Jan 17, 2026 | 6.48% (0.06482) | 90.80th | v4 (v2025.03.14) |
| Dec 28, 2025 | 4.88% (0.04880) | 89.22th | v4 (v2025.03.14) |
| Dec 27, 2025 | 3.02% (0.03023) | 86.26th | v4 (v2025.03.14) |
| Oct 28, 2025 | 4.88% (0.04880) | 89.07th | v4 (v2025.03.14) |
| Oct 27, 2025 | 3.02% (0.03023) | 86.14th | v4 (v2025.03.14) |
| Oct 1, 2025 | 4.88% (0.04880) | 89.16th | v4 (v2025.03.14) |
| Aug 19, 2025 | 2.61% (0.02607) | 85.04th | v4 (v2025.03.14) |
| Jul 30, 2025 | 4.05% (0.04049) | 88.07th | v4 (v2025.03.14) |
| Jun 21, 2025 | 6.48% (0.06482) | 90.62th | v4 (v2025.03.14) |
| Mar 30, 2025 | 2.47% (0.02470) | 83.85th | v4 (v2025.03.14) |
| Mar 29, 2025 | 8.06% (0.08061) | 86.61th | v4 (v2025.03.14) |
| Mar 17, 2025 | 2.55% (0.02554) | 84.47th | v4 (v2025.03.14) |
| Dec 12, 2024 | 3.59% (0.03592) | 92.00th | v3 (v2023.03.01) |
| Apr 24, 2023 | 3.59% (0.03592) | 90.25th | v3 (v2023.03.01) |
| Mar 12, 2023 | 3.38% (0.03381) | 89.92th | v3 (v2023.03.01) |
| Mar 7, 2023 | 2.84% (0.02845) | 89.12th | v3 (v2023.03.01) |
| Mar 6, 2023 | 3.78% (0.03779) | 85.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 3.78% (0.03779) | 84.01th | v2 (v2022.01.01) |
| Feb 4, 2022 | 3.78% (0.03779) | 67.21th | v2 (v2022.01.01) |
References (19)
- http://lists.fedoraproject.org/pipermail/package-announce/2016-May/183736.html vendor-advisoryx_refsource_FEDORA
- http://lists.opensuse.org/opensuse-updates/2016-05/msg00086.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-updates/2016-06/msg00027.html vendor-advisoryx_refsource_SUSE
- http://php.net/ChangeLog-5.php x_refsource_CONFIRMPatch
- http://php.net/ChangeLog-7.php x_refsource_CONFIRMPatch
- http://rhn.redhat.com/errata/RHSA-2016-2750.html vendor-advisoryx_refsource_REDHAT
- http://www.debian.org/security/2016/dsa-3602 vendor-advisoryx_refsource_DEBIAN
- http://www.openwall.com/lists/oss-security/2016/05/05/21 mailing-listx_refsource_MLIST
- http://www.securityfocus.com/bid/90173 vdb-entryx_refsource_BID
- https://access.redhat.com/security/cve/CVE-2016-4538 Vendor Advisory
- https://bugs.php.net/bug.php?id=72093 x_refsource_CONFIRMExploit
- https://bugzilla.redhat.com/show_bug.cgi?id=1332860 Issue Tracking
- https://git.php.net/?p=php-src.git%3Ba=commit%3Bh=d650063a0457aec56364e4005a636dc6c401f9cd x_refsource_CONFIRM
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05240731 x_refsource_CONFIRM
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05320149 x_refsource_CONFIRM
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722 x_refsource_CONFIRM
- https://nvd.nist.gov/vuln/detail/CVE-2016-4538
- https://security.gentoo.org/glsa/201611-22 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2016-4538
Change history (0)
No recorded changes yet.