php: race condition when handling many concurrent signals may lead to memory corruption
Published Feb 2, 2011
4.3
MEDIUMCVSS 2.0
EPSS 0.80%
Description
Race condition in the PCNTL extension in PHP before 5.3.4, when a user-defined signal handler exists, might allow context-dependent attackers to cause a denial of service (memory corruption) via a large number of concurrent signals.
Affected products
No data.
- ≤ 5.3.3
- 1.0
- 2.0
- 2.0b10
- 3.0
- 3.0.1
- 3.0.2
- 3.0.3
- 3.0.4
- 3.0.5
- 3.0.6
- 3.0.7
- 3.0.8
- 3.0.9
- 3.0.10
- 3.0.11
- 3.0.12
- 3.0.13
- 3.0.14
- 3.0.15
- 3.0.16
- 3.0.17
- 3.0.18
- 4.0
- 4.0
- 4.0
- 4.0
- 4.0
- 4.0
- 4.0.0
- 4.0.1
- 4.0.2
- 4.0.3
- 4.0.4
- 4.0.5
- 4.0.6
- 4.0.7
- 4.1.0
- 4.1.1
- 4.1.2
- 4.2.0
- 4.2.1
- 4.2.2
- 4.2.3
- 4.3.0
- 4.3.1
- 4.3.2
- 4.3.3
- 4.3.4
- 4.3.5
- 4.3.6
- 4.3.7
- 4.3.8
- 4.3.9
- 4.3.10
- 4.3.11
- 4.4.0
- 4.4.1
- 4.4.2
- 4.4.3
- 4.4.4
- 4.4.5
- 4.4.6
- 4.4.7
- 4.4.8
- 4.4.9
- 5.3.0
- 5.3.1
- 5.3.2
No data.
Red Hat Enterprise Linux 4
php
Will not fix
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
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 4 | php | Will not fix | n/a |
| 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 |
No package ranges for this CVE.
Remediation
Red Hat statement
Red Hat does not consider this issue to be a security vulnerability since no trust boundary is crossed. Any process able to send signals to a running PHP process can terminate it by sending a carefully-chosen signal.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:M/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
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.80% (0.00800) | 54.98th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.80% (0.00800) | 51.62th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.32% (0.00322) | 52.95th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.35% (0.00348) | 72.56th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.35% (0.00348) | 70.92th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.35% (0.00348) | 67.20th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.02% (0.01018) | 40.69th | v2 (v2022.01.01) |
| Sep 10, 2022 | 1.02% (0.01018) | 38.88th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.02% (0.01018) | 36.86th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.02% (0.01018) | 19.50th | v2 (v2022.01.01) |
References (8)
- http://bugs.php.net/52784 x_refsource_CONFIRMPatch
- http://www.php.net/ChangeLog-5.php x_refsource_CONFIRM
- https://access.redhat.com/security/cve/CVE-2011-0753 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=674705 Issue Tracking
- https://exchange.xforce.ibmcloud.com/vulnerabilities/65431 vdb-entryx_refsource_XF
- https://nvd.nist.gov/vuln/detail/CVE-2011-0753
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12271 vdb-entrysignaturex_refsource_OVAL
- https://www.cve.org/CVERecord?id=CVE-2011-0753
| Link | Providers | Tags |
|---|---|---|
| http://bugs.php.net/52784 | x_refsource_CONFIRMPatch | |
| http://www.php.net/ChangeLog-5.php | x_refsource_CONFIRM | |
| https://access.redhat.com/security/cve/CVE-2011-0753 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=674705 | Issue Tracking | |
| https://exchange.xforce.ibmcloud.com/vulnerabilities/65431 | vdb-entryx_refsource_XF | |
| https://nvd.nist.gov/vuln/detail/CVE-2011-0753 | ||
| https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12271 | vdb-entrysignaturex_refsource_OVAL | |
| https://www.cve.org/CVERecord?id=CVE-2011-0753 |
Change history (0)
No recorded changes yet.