VulnerabilityPublished 12 May 2026Updated 19 May 2026

CVE-2026-8368: OALDERS LWP::UserAgent · Insufficiently Protected Credentials

Affects OALDERS LWP::UserAgentSource CVE Database V5

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Not known to be exploited · CVSS 6.5 Medium : upgrade to 6.83 when convenient.

Data as of 29 Oct 2026, 19:04 UTC

CVSS 3.1 base score

6.5Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 18% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 6.83

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
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: 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: 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 12 May 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 LWP::UserAgent and libwww-perl to 6.83.

Affected software

Product	Affected	Fixed in
OALDERSLWP::UserAgent	Affected <6.83	Fixed in 6.83
GitHublibwww-perl`pkg:github/libwww-perl`Other threats	Affected <6.83	Fixed in 6.83

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

AI-suggested

If you cannot patch yet, users should avoid following redirects to untrusted or attacker-controlled hosts when using vulnerable versions of LWP::UserAgent. Consider implementing manual redirect handling that strips sensitive headers or upgrading to a version confirmed to have addressed this issue once available.

Description

CVE-2026-8368 is a vulnerability in OALDERS LWP::UserAgent versions before 6.83 for Perl where Authorization and Proxy-Authorization headers are leaked during cross-origin redirects. The redirect handler fails to strip these sensitive headers on 3xx responses, sending them unchanged to the redirect target, which can be an attacker-controlled host. This results in disclosure of the caller's credentials. The vulnerability has a medium severity with a CVSS score of 6.5.

Impact

The vulnerability allows an attacker controlling a redirect destination to receive the victim's Authorization and Proxy-Authorization headers, potentially exposing sensitive credentials. This can lead to unauthorized access to resources or services that rely on these credentials. There is no indication of impact on integrity or availability, only confidentiality is affected.

Summary

LWP::UserAgent versions prior to 6.83 for Perl improperly handle HTTP 3xx redirects by not removing Authorization and Proxy-Authorization headers before following the redirect. While the redirect handler removes Host and Cookie headers, it leaves these sensitive authentication headers intact, allowing them to be sent to potentially malicious redirect destinations. This behavior can lead to credential leakage if the redirect points to an attacker-controlled host. The vulnerability is classified under CWE-522 (Insufficiently Protected Credentials) and has a CVSS 3.1 base score of 6.5, indicating a medium severity network attack vector with low attack complexity and no user interaction required.

CWE-522Insufficiently Protected Credentials (opens in a new tab)
Class weaknessOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.
Architecture and Design
Use an appropriate security mechanism to protect the credentials.
Architecture and Design
Make appropriate use of cryptography to protect the credentials.
Implementation
Use industry standards to protect the credentials (e.g. LDAP, keystore, etc.).
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V2.10.3 (opens in a new tab)
V2.8.5 (opens in a new tab)
V2.8.4 (opens in a new tab)
Attack patterns
Session Sidejacking (opens in a new tab)
Signature Spoofing by Key Theft (opens in a new tab)
Password Recovery Exploitation (opens in a new tab)
Kerberoasting (opens in a new tab)
Modify Existing Service (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 3 Jun 2026, 21:19 UTC

WeaknessesCWE-522

Technical details

References

Community reviews

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