Evidence used
- No CISA KEV confirmation is currently recorded.
- A structured source references public exploit or proof-of-concept material.
- EPSS is 0.18% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-77831High confidence
Algorithmic-complexity denial of service in AshPaperTrail full-diff list tracking
ash-project · ash paper trail
2.1LowCVSS 4.0
Within 7 days
Patch availableLow technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityLow→Operational priority:Low, 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.
- Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
- Confirm that the asset runs ash-project ash paper trail 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.
Low technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available01
What, why and how
Inefficient Algorithmic Complexity vulnerability in ash-project ash_paper_trail allows a user who can submit a large array attribute to a paper-trailed create or update action to cause a denial of service through excessive CPU and memory use. With full-diff change tracking, AshPaperTrail.ChangeBuilders.FullDiff.ListChange pairs each prior array element against the new list by rebuilding the remaining-elements accumulator with acc ++ [tuple] on every step, copying the growing list each time, so the pairing scales cubically in the array length. Nothing bounds the length and the value comes straight from action input, so one request carrying a large accepted {:array, _} attribute forces tens of seconds of CPU and multi-gigabyte allocations. This issue affects ash_paper_trail: from 0.1.1 before 0.7.0.
What
Inefficient Algorithmic Complexity vulnerability in ash-project ash_paper_trail allows a user who can submit a large array attribute to a paper-trailed create or update action to cause a denial of service through excessive CPU and memory use. With full-diff change tracking, AshPaperTrail.ChangeBuilders.FullDiff.ListChange pairs each prior array element against the new list by rebuilding the remaining-elements accumulator with acc ++ [tuple] on every step, copying the growing list each time, so the pairing scales cubically in the array length. Nothing bounds the length and the value comes straight from action input, so one request carrying a large accepted {:array, _} attribute forces tens of seconds of CPU and multi-gigabyte allocations. This issue affects ash_paper_trail: from 0.1.1 before 0.7.0.
Why
An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
How
An attacker operating through local access may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.
What
Inefficient Algorithmic Complexity vulnerability in ash-project ash_paper_trail allows a user who can submit a large array attribute to a paper-trailed create or update action to cause a denial of service through excessive CPU and memory use. With full-diff change tracking, AshPaperTrail.ChangeBuilders.FullDiff.ListChange pairs each prior array element against the new list by rebuilding the remaining-elements accumulator with acc ++ [tuple] on every step, copying the growing list each time, so the pairing scales cubically in the array length. Nothing bounds the length and the value comes straight from action input, so one request carrying a large accepted {:array, _} attribute forces tens of seconds of CPU and multi-gigabyte allocations. This issue affects ash_paper_trail: from 0.1.1 before 0.7.0.
Why
An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
How
An attacker operating through local access may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.
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 Reference recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.CISA Vulnrichment records proof-of-concept exploitation in its SSVC data. BlackTree has not independently executed or validated exploit material.
- Likely attack path
- local access → Inefficient Algorithmic Complexity → disrupt the affected service
- Attack surface
- Local
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Not a CVSS 4.0 base metric
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-407 ↗
CWE-407: Inefficient Algorithmic Complexity. An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NCommon Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.
AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.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.VCNoneVulnerable-system confidentiality: No direct loss is represented by this metric.VINoneVulnerable-system integrity: No direct loss is represented by this metric.VALowVulnerable-system availability: A successful attack can cause a limited loss.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
- The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
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
- 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 30 Aug 2026 · Last source change 31 Aug 2026, 14:52 UTC · CWE-407 · Inefficient Algorithmic Complexity
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-30
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-68144
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- Public exploit evidencePublic exploit evidence changed from No public exploit to Public exploit reference.CVE.org ↗
- Before
- No public exploit
- After
- Public exploit reference
- ENISA EUVD mappingEUVD-2026-68144 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-68144"}
- Affected versionsThe structured affected or fixed version information changed.CNA ↗
- Before
- 0.1.1 < 0.7.0; 449cd2a93416853066378fa61c715e89f80dc854 < e781f5d8840b07d57db99f9a4728298837d7b3a8 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- After
- ash paper trail: 0.1.1 < 0.7.0, 449cd2a93416853066378fa61c715e89f80dc854 < e781f5d8840b07d57db99f9a4728298837d7b3a8 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
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.