CHORNY Apache::Session::Generate::MD5 up to 1.94 on Perl Default Session ID Generator rand generation of predictable numbers or identifiers

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6.4	$0-$5k	0.00

Summaryinfo

A vulnerability classified as problematic was found in CHORNY Apache::Session::Generate::MD5 up to 1.94 on Perl. This issue affects the function rand of the component Default Session ID Generator. Executing a manipulation can lead to generation of predictable numbers or identifiers. This vulnerability is registered as CVE-2025-40931. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability has been found in CHORNY Apache::Session::Generate::MD5 up to 1.94 on Perl and classified as problematic. This vulnerability affects the function rand of the component Default Session ID Generator. The manipulation with an unknown input leads to a generation of predictable numbers or identifiers vulnerability. The CWE definition for the vulnerability is CWE-340. The product uses a scheme that generates numbers or identifiers that are more predictable than required. As an impact it is known to affect confidentiality. CVE summarizes:

Apache::Session::Generate::MD5 versions through 1.94 for Perl create insecure session id. Apache::Session::Generate::MD5 generates session ids insecurely. The default session id generator returns a MD5 hash seeded with the built-in rand() function, the epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage. Predicable session ids could allow an attacker to gain access to systems.

The weakness was published by Robert Rothenberg. The advisory is shared for download at metacpan.org. This vulnerability was named CVE-2025-40931 since 04/16/2025. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1600.001.

The vulnerability scanner Nessus provides a plugin with the ID 301112 (Linux Distros Unpatched Vulnerability : CVE-2025-40931), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (301112). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

• CHORNY

Name

• Apache::Session::Generate::MD5

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31
• 1.32
• 1.33
• 1.34
• 1.35
• 1.36
• 1.37
• 1.38
• 1.39
• 1.40
• 1.41
• 1.42
• 1.43
• 1.44
• 1.45
• 1.46
• 1.47
• 1.48
• 1.49
• 1.50
• 1.51
• 1.52
• 1.53
• 1.54
• 1.55
• 1.56
• 1.57
• 1.58
• 1.59
• 1.60
• 1.61
• 1.62
• 1.63
• 1.64
• 1.65
• 1.66
• 1.67
• 1.68
• 1.69
• 1.70
• 1.71
• 1.72
• 1.73
• 1.74
• 1.75
• 1.76
• 1.77
• 1.78
• 1.79
• 1.80
• 1.81
• 1.82
• 1.83
• 1.84
• 1.85
• 1.86
• 1.87
• 1.88
• 1.89
• 1.90
• 1.91
• 1.92
• 1.93
• 1.94

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.4

VulDB Base Score: 3.7
VulDB Temp Score: 3.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 9.1
ADP CISA Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Generation of predictable numbers or identifiers
CWE: CWE-340 / CWE-331 / CWE-330
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 301112
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-40931

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/16/2025 CVE reserved
03/05/2026 +323 days Advisory disclosed
03/05/2026 +0 days VulDB entry created
03/10/2026 +5 days VulDB entry last update

Sourcesinfo

Advisory: metacpan.org
Researcher: Robert Rothenberg
Status: Not defined

CVE: CVE-2025-40931 (🔒)
GCVE (CVE): GCVE-0-2025-40931
GCVE (VulDB): GCVE-100-348880

Entryinfo

Created: 03/05/2026 07:12
Updated: 03/10/2026 18:07
Changes: 03/05/2026 07:12 (55), 03/06/2026 11:07 (11), 03/07/2026 18:39 (2), 03/10/2026 18:07 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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