Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.44% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-23892High confidence
OctoPrint has Timing Side-Channel Vulnerability in API Key Authentication
OctoPrint · OctoPrint
Official source article: GitHub GHSA-XG4X-W2J3-57H6 ↗. Check the applicable product and release in the original source.
6.0MediumCVSS 4.0
Scheduled
Patch availableMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Medium, unchanged from published severity.unchanged
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs OctoPrint OctoPrint and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Open-source package ranges1 source-attributed range
These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.
| Ecosystem and package | Affected range | First fixed version | Evidence |
|---|---|---|---|
| pipOctoPrint | < 1.11.6 | 1.11.6 | GitHub advisory ↗upstream repository advisory · 2 Feb 2026 |
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Patch available01
What, why and how
OctoPrint provides a web interface for controlling consumer 3D printers. OctoPrint versions up to and including 1.11.5 are affected by a (theoretical) timing attack vulnerability that allows API key extraction over the network. Due to using character based comparison that short-circuits on the first mismatched character during API key validation, rather than a cryptographical method with static runtime regardless of the point of mismatch, an attacker with network based access to an affected OctoPrint could extract API keys valid on the instance by measuring the response times of the denied access responses and guess an API key character by character. The vulnerability is patched in version 1.11.6. The likelihood of this attack actually working is highly dependent on the network's latency, noise and similar parameters. An actual proof of concept was not achieved so far. Still, as always administrators are advised to not expose their OctoPrint instance on hostile networks, especially not on the public Internet.
What
OctoPrint provides a web interface for controlling consumer 3D printers. OctoPrint versions up to and including 1.11.5 are affected by a (theoretical) timing attack vulnerability that allows API key extraction over the network. Due to using character based comparison that short-circuits on the first mismatched character during API key validation, rather than a cryptographical method with static runtime regardless of the point of mismatch, an attacker with network based access to an affected OctoPrint could extract API keys valid on the instance by measuring the response times of the denied access responses and guess an API key character by character. The vulnerability is patched in version 1.11.6. The likelihood of this attack actually working is highly dependent on the network's latency, noise and similar parameters. An actual proof of concept was not achieved so far. Still, as always administrators are advised to not expose their OctoPrint instance on hostile networks, especially not on the public Internet.
Why
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.
How
An attacker operating through an adjacent network may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
OctoPrint provides a web interface for controlling consumer 3D printers. OctoPrint versions up to and including 1.11.5 are affected by a (theoretical) timing attack vulnerability that allows API key extraction over the network. Due to using character based comparison that short-circuits on the first mismatched character during API key validation, rather than a cryptographical method with static runtime regardless of the point of mismatch, an attacker with network based access to an affected OctoPrint could extract API keys valid on the instance by measuring the response times of the denied access responses and guess an API key character by character. The vulnerability is patched in version 1.11.6. The likelihood of this attack actually working is highly dependent on the network's latency, noise and similar parameters. An actual proof of concept was not achieved so far. Still, as always administrators are advised to not expose their OctoPrint instance on hostile networks, especially not on the public Internet.
Why
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.
How
An attacker operating through an adjacent network may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- an adjacent network → Observable Timing Discrepancy → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Adjacent
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- High: exploitation depends on specific conditions
- Security boundary
- Not a CVSS 4.0 base metric
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-208 ↗
CWE-208: Observable Timing Discrepancy. 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.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NCommon Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.
AVAdjacentAttack vector: The attacker must be on an adjacent or logically close network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.ATPresentAttack requirements: A particular deployment or execution condition must be present.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VINoneVulnerable-system integrity: No direct loss is represented by this metric.VANoneVulnerable-system availability: No direct loss is represented by this metric.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Affected
- OctoPrint: < 1.11.6
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 27 Jan 2026 · Last source change 27 Jan 2026, 19:14 UTC · CWE-208 · Observable Timing Discrepancy
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-4775
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.