CVE-2026-112915VulnerabilityPublished 9 Nov 2026

gam · filelock ReadWriteLock: a crafted lock database makes every acquire stall or hang regardless of timeout

Affects gamSource GCVE Database

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Authoritative record:CVE-2026-112915· Medium 5.5

Not known to be exploited · CVSS 5.5 Medium.

Data as of 9 Nov 2026, 20:05 UTC

CVSS 3.1 base score

5.5Medium

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

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

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

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

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
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: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 20 Oct 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 9 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.

What to do

Affected software

Product	Affected	Fixed in
Homebrewgam`pkg:brew/gam`Other threats	Affected >=7.50.00	Fixed in–

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AI-suggested

This issue requires that the lock database file path be protected against unauthorized write or replacement by untrusted local users. Use sticky bit on shared directories to prevent unauthorized file replacement, ensure directory and file permissions restrict write access to trusted users only, and avoid sharing lock databases writable by multiple users. The vendor has not provided an official patch or fix in the advisory; therefore, administrators should apply these access control mitigations to prevent exploitation.

Description

A vulnerability in filelock's ReadWriteLock and AsyncReadWriteLock components allows a local user with write access to the lock database file path to cause every acquire operation to stall or hang indefinitely, ignoring timeout and blocking settings. This is achieved by placing a crafted SQLite database file at the lock path, which triggers expensive schema loading operations that consume significant CPU and memory resources. The issue affects filelock versions 3.20.4 through 4.2.0 and results in a denial of service condition without compromising confidentiality or integrity.

Impact

An attacker with local write access to the lock database file path can cause all processes using the ReadWriteLock to stall or hang indefinitely during lock acquisition, ignoring timeout and blocking parameters. This results in a denial of service condition affecting availability only. There is no impact on confidentiality or integrity. The stall can consume high CPU and memory resources, and the process must be killed to recover.

Summary

The ReadWriteLock and AsyncReadWriteLock in filelock run `PRAGMA journal_mode=MEMORY` on a fresh SQLite connection for every acquire operation, causing SQLite to load the entire schema of the file at the lock path. A local attacker who can create or overwrite this file can supply a crafted SQLite database that causes the acquire call to stall or spin indefinitely, ignoring the caller's timeout and blocking flags. This leads to high CPU usage and large memory allocation (~1 GB) during the stall. The vulnerability requires the attacker to have local write access to the lock file path, which is possible if the directory is writable and not sticky or if the lock database file is writable by others. The impact is availability only; no confidentiality or integrity loss occurs. The affected versions are filelock 3.20.4 through 4.2.0. The CVSS 3.1 score is 5.5 (medium) with local attack vector, low privileges, and high availability impact.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 9 Nov 2026, 20:05 UTC

Technical details

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