CVE-2023-41329 [Low] | Security Bypass in Python Wiremock

WireMock is a tool for mocking HTTP services. The proxy mode of WireMock, can be protected by the network restrictions configuration, as documented in Preventing proxying to and recording from specific target addresses. These restrictions can be configured using the domain names, and in such a case the configuration is vulnerable to the DNS rebinding attacks. A similar patch was applied in WireMock 3.0.0-beta-15 for the WireMock Webhook Extensions. The root cause of the attack is a defect in the logic which allows for a race condition triggered by a DNS server whose address expires in between the initial validation and the outbound network request that might go to a domain that was supposed to be prohibited. Control over a DNS service is required to exploit this attack, so it has high execution complexity and limited impact. This issue has been addressed in version 2.35.1 of wiremock-jre8 and wiremock-jre8-standalone, version 3.0.3 of wiremock and wiremock-standalone, version 2.6.1 of the python version of wiremock, and versions 2.35.1-1 and 3.0.3-1 of the wiremock/wiremock Docker container. Users are advised to upgrade. Users unable to upgrade should either configure firewall rules to define the list of permitted destinations or to configure WireMock to use IP addresses instead of the domain names.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.49%	0.57%	+0.08%
2	2026-06-01	0.30%	0.49%	+0.19%
3	2026-03-15	—	0.30%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.49%

0.57%

+0.08%

2026-06-01

0.30%

0.49%

+0.19%

2026-03-15

—

0.30%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
3.9	3.1	LOW	`CVSS:3.1/AV:A/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L` Click to expand Attack vector (AV:A) Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:H) They need powerful rights—admin, root, or similar—before this pays off. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:L) Some sensitive info could get out, but not a total data dump. Integrity (I:L) Attackers could change some data, but it’s limited—not everything goes. Availability (A:L) Might cause slowdowns, glitches, or partial disruption—not a full brick.	0.5	3.4	[email protected]
6.6	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:H) They need powerful rights—admin, root, or similar—before this pays off. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.7	5.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

3.9

3.1

LOW

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

Attack vector (AV:A): Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H): They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L): Some sensitive info could get out, but not a total data dump.
Integrity (I:L): Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L): Might cause slowdowns, glitches, or partial disruption—not a full brick.

0.5

3.4

[email protected]

6.6

3.1

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H): They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.7

5.9

[email protected]

Affected software / configurations for CVE-2023-41329

Vendor	Product	Version	Raw CPE
wiremock	python_wiremock	< 2.6.1	cpe:2.3:a:wiremock:python_wiremock::::::::
wiremock	studio	<= 2.32.0-17	cpe:2.3:a:wiremock:studio::::::::
wiremock	wiremock	< 2.35.1	cpe:2.3:a:wiremock:wiremock::::::::
wiremock	wiremock	>= 3.0.0, < 3.0.3	cpe:2.3:a:wiremock:wiremock::::::::
wiremock	wiremock_docker	>= 2.0.0, < 2.35.1-1	cpe:2.3:a:wiremock:wiremock_docker::::::::
wiremock	wiremock_docker	>= 3.0.0, < 3.0.3-1	cpe:2.3:a:wiremock:wiremock_docker::::::::

References for CVE-2023-41329

URL	Tags
https://github.com/wiremock/wiremock/security/advisories/GHSA-pmxq-pj47-j8j4	Vendor Advisory
https://wiremock.org/docs/configuration/#preventing-proxying-to-and-recording-from-specific-target-addresses	Product

URL

CVE-2023-41329 | Domain restrictions bypass via DNS Rebinding in WireMock and WireMock Studio

Exploit prediction scoring system (EPSS) score for CVE-2023-41329

Common vulnerability scoring system (CVSS) metrics for CVE-2023-41329

Weakness enumeration for CVE-2023-41329

GitHub Security Advisory for CVE-2023-41329

Affected software / configurations for CVE-2023-41329

References for CVE-2023-41329