The mcrypt_create_iv function in ext/mcrypt/mcrypt.c in PHP before 4.4.7, 5.2.1, and possibly 5.0.x and other PHP 5 versions, calls php_rand_r with an uninitialized seed variable and therefore always generates the same initialization vector (IV), which might allow context-dependent attackers to decrypt certain data more easily because of the guessable encryption keys
Published May 16, 2007
2.6
LOWCVSS 2.0
EPSS 1.90%
Description
The mcrypt_create_iv function in ext/mcrypt/mcrypt.c in PHP before 4.4.7, 5.2.1, and possibly 5.0.x and other PHP 5 versions, calls php_rand_r with an uninitialized seed variable and therefore always generates the same initialization vector (IV), which might allow context-dependent attackers to decrypt certain data more easily because of the guessable encryption keys.
Affected products
No data.
- ≥ 4.4.0 · < 4.4.7
- ≥ 5.0.0 · < 5.2.2
- 4.0.1
- 4.0.1
- 4.0.1
- 4.0.2
- 4.0.3
- 4.0.3
- 4.0.4
- 4.0.5
- 4.0.6
- 4.0.7
- 4.0.7
- 4.0.7
- 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
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
Red Hat statement
Not vulnerable. This issue did not affect the versions of php as shipped with Red Hat Enterprise Linux 2.1, 3, 4, or 5, or Red Hat Application Stack 1, or 2, as the packages shipped are not compiled with the mcrypt extension affected by this issue.
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:H/Au:N/C:P/I:N/A:N
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 (15 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 1.90% (0.01896) | 78.89th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.85% (0.01845) | 76.20th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.45% (0.00447) | 61.39th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.72% (0.00717) | 81.20th | v3 (v2023.03.01) |
| Jul 11, 2024 | 0.72% (0.00717) | 80.71th | v3 (v2023.03.01) |
| Apr 26, 2024 | 0.64% (0.00641) | 78.96th | v3 (v2023.03.01) |
| Mar 19, 2024 | 0.52% (0.00521) | 76.37th | v3 (v2023.03.01) |
| Feb 10, 2024 | 0.41% (0.00408) | 73.15th | v3 (v2023.03.01) |
| Jan 3, 2024 | 0.42% (0.00423) | 71.59th | v3 (v2023.03.01) |
| Sep 10, 2023 | 0.45% (0.00451) | 72.02th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.49% (0.00490) | 72.39th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.54% (0.01537) | 74.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.54% (0.01537) | 72.41th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
No CWE recorded.
References (13)
- http://blog.php-security.org/archives/80-Watching-the-PHP-CVS.html x_refsource_MISCVendor Advisory
- http://bugs.php.net/bug.php?id=40999 x_refsource_CONFIRMVendor Advisory
- http://cvs.php.net/viewvc.cgi/php-src/ext/mcrypt/mcrypt.c?r1=1.91.2.3.2.9&r2=1.91.2.3.2.10 x_refsource_CONFIRMVendor Advisory
- http://osvdb.org/36087 vdb-entryx_refsource_OSVDBBroken Link
- http://secunia.com/advisories/26895 third-party-advisoryx_refsource_SECUNIABroken Link
- http://www.fortheloot.com/public/mcrypt.patch x_refsource_MISCExploitPatchThird Party Advisory
- http://www.mandriva.com/security/advisories?name=MDKSA-2007:187 vendor-advisoryx_refsource_MANDRIVABroken Link
- http://www.novell.com/linux/security/advisories/2007_15_sr.html vendor-advisoryx_refsource_SUSEThird Party Advisory
- http://www.php.net/ChangeLog-5.php x_refsource_CONFIRMVendor Advisory
- http://www.securityfocus.com/bid/23984 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2007-2727 Vendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2007-2727
- https://www.cve.org/CVERecord?id=CVE-2007-2727
Change history (0)
No recorded changes yet.