VulnerabilityPublished 6 Aug 2026

CVE-2025-49506: Apache Portable Runtime Utility · Timing Side Channel

Affects Apache Portable Runtime UtilitySource CVE Database V5

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Not known to be exploited · CVSS 7.5 High · fixed in 1.6.4 : patch Apache Portable Runtime Utility soon.

Data as of 5 Nov 2026, 23:24 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 32% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 1.6.4

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-73wm-47mq-62r5

What to do

Affected software

Product	Affected	Fixed in
Apache Software FoundationApache Portable Runtime Utility	Affected >=1.2.0 <=1.6.3	Fixed in–
Mavenorg.apache.apr/apr-util`pkg:maven/org.apache.apr/apr-util`Other threats	Affected =1.2.0 <=1.6.3	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Users should upgrade to APR-util version 1.6.4, which fixes the timing discrepancy issue in apr_password_validate(). No other mitigations are indicated. Patch status is confirmed by the recommendation to upgrade to 1.6.4.

Description

CVE-2025-49506 is a timing side-channel vulnerability in the Apache Portable Runtime Utility (APR-util) affecting versions up to and including 1.6.3. The apr_password_validate() function did not perform password or hash comparisons in constant time, potentially allowing attackers to infer sensitive information via timing discrepancies on platforms lacking the crypt() function, such as Windows, BeOS, NetWare, or Android. The issue is fixed in version 1.6.4.

Impact

An attacker could potentially exploit the timing discrepancy to infer password or hash contents, leading to information disclosure. The vulnerability does not impact integrity or availability but poses a confidentiality risk. The CVSS score of 7.5 (high) reflects the network attack vector, low complexity, no privileges required, no user interaction, and high confidentiality impact.

Summary

The vulnerability in APR-util versions up to 1.6.3 involves the apr_password_validate() function, which compares passwords and hashes in a non-constant-time manner. This behavior can leak information through timing side channels, especially on platforms without the crypt() function. This flaw is classified under CWE-208 (Observable Timing Discrepancy). Users are advised to upgrade to APR-util version 1.6.4 where this issue has been addressed.

CWE-208Observable Timing Discrepancy (opens in a new tab)
Base weakness
Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not.
OWASP Cheat Sheets
Error Handling (opens in a new tab)
Logging (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.4 (opens in a new tab)
V14.3.3 (opens in a new tab)
V7.3.3 (opens in a new tab)
Attack patterns
Cross-Domain Search Timing (opens in a new tab)
Application Fingerprinting (opens in a new tab)
System Footprinting (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 13 Aug 2026, 17:00 UTC

WeaknessesCWE-208

Technical details

References

Community reviews

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