VulnerabilityPublished 29 Oct 2026

CVE-2026-112936: filelock · ReadWriteLock follows a symlink at the lock path into SQLite

Affects hatchSource GCVE Database

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Authoritative record:CVE-2026-112936· Medium 6.1

Not known to be exploited · CVSS 6.1 Medium : upgrade to 1.18.1_2 when convenient.

Data as of 30 Oct 2026, 09:00 UTC

CVSS 3.1 base score

6.1Medium

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

Patch: Available – fixed in 1.18.1_2

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

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

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: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

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 29 Oct 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

Upgrade hatch to 1.18.1_2.

Affected software

Product	Affected	Fixed in
Homebrewhatch`pkg:brew/hatch`Other threats	Affected >=1.16.4 <1.18.1_2	Fixed in 1.18.1_2

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

AI-suggested

A fix is available in hatch version 1.18.1_2. Users should upgrade to this version or later. As a workaround, ensure that ReadWriteLock paths are located in directories writable only by trusted users to prevent attackers from planting symlinks.

Description

The ReadWriteLock and AsyncReadWriteLock classes in the hatch product resolve lock file paths by following symlinks, which allows a local attacker with write access to the lock directory to manipulate the lock behavior. This can cause the victim process to create files at unintended locations, break mutual exclusion by allowing multiple processes to hold the write lock simultaneously, and interfere with SQLite database locking. The vulnerability affects hatch versions from 1.16.4 up to but not including 1.18.1_2 and has a CVSS score of 6.1 (medium severity).

Impact

A local attacker with write permissions to the lock directory can cause victim processes to create files they own at arbitrary paths, interfere with SQLite database locking by causing 'database is locked' errors in unrelated applications, and break mutual exclusion by allowing multiple victim processes to hold the write lock simultaneously. This can lead to resource corruption and denial of service conditions.

Summary

The vulnerability arises because ReadWriteLock and AsyncReadWriteLock use pathlib.Path.resolve() on the lock path, which follows the final symlink, and then pass this resolved path to sqlite3.connect() without preventing symlink usage. This allows a local attacker who can create names in the lock directory to plant a symlink that causes the victim's process to create or lock files at attacker-controlled paths. This breaks the intended mutual exclusion guarantees of the lock, potentially causing resource corruption or denial of service by locking unrelated SQLite databases. The issue is reproducible on Linux, macOS, and Windows 11. Other lock classes like FileLock do not follow symlinks and are not affected. The vulnerability is fixed in hatch version 1.18.1_2.

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Affected software

Description

AI analysisMachine-generated, updated 30 Oct 2026, 09:00 UTC

Technical details

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