Evidence used
- No CISA KEV confirmation is currently recorded.
- A structured source references public exploit or proof-of-concept material.
- EPSS is 0.35% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-86766High confidence
Snipe-IT 8.6.3 Race Condition via Consumable Checkout
grokability · snipe-it
Official source article: GitHub GHSA-X4G2-87XC-M5JM ↗. Check the applicable product and release in the original source.
7.1HighCVSS 4.0
Within 7 days
Patch availableHigh 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 severityHigh→Operational priority:Critical, raised one band.upgradedsince 9 Sep 2026
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict the affected network interface to trusted sources where business-safe.
- Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
- Confirm that the asset runs grokability snipe-it 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.
High 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
Snipe-IT versions up to and including 8.6.3 contain a race condition (TOCTOU) in the consumable checkout API endpoint (POST /api/v1/consumables/{consumable_id}/checkout). The requested quantity is validated against the number of remaining units before the database transaction begins, and the transaction then creates the checkout records without locking the consumable row or re-checking availability. An authenticated user with permission to check out consumables can submit concurrent checkout requests for the same consumable so that both requests pass the availability check and succeed, over-allocating stock and driving the remaining inventory negative (e.g., a consumable with 1 remaining unit ends at -1 after two concurrent 1-unit checkouts). The issue is fixed in 8.7.0, which re-fetches the parent row under lockForUpdate inside the transaction and re-validates availability.
What
Snipe-IT versions up to and including 8.6.3 contain a race condition (TOCTOU) in the consumable checkout API endpoint (POST /api/v1/consumables/{consumable_id}/checkout). The requested quantity is validated against the number of remaining units before the database transaction begins, and the transaction then creates the checkout records without locking the consumable row or re-checking availability. An authenticated user with permission to check out consumables can submit concurrent checkout requests for the same consumable so that both requests pass the availability check and succeed, over-allocating stock and driving the remaining inventory negative (e.g., a consumable with 1 remaining unit ends at -1 after two concurrent 1-unit checkouts). The issue is fixed in 8.7.0, which re-fetches the parent row under lockForUpdate inside the transaction and re-validates availability.
Why
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
Snipe-IT versions up to and including 8.6.3 contain a race condition (TOCTOU) in the consumable checkout API endpoint (POST /api/v1/consumables/{consumable_id}/checkout). The requested quantity is validated against the number of remaining units before the database transaction begins, and the transaction then creates the checkout records without locking the consumable row or re-checking availability. An authenticated user with permission to check out consumables can submit concurrent checkout requests for the same consumable so that both requests pass the availability check and succeed, over-allocating stock and driving the remaining inventory negative (e.g., a consumable with 1 remaining unit ends at -1 after two concurrent 1-unit checkouts). The issue is fixed in 8.7.0, which re-fetches the parent row under lockForUpdate inside the transaction and re-validates availability.
Why
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
How
An attacker operating through a network path may attempt exploitation with low privileges. 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 Reference recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
- Likely attack path
- a network path → Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- Low: a basic authenticated account is required
- 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-362 ↗
CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition'). The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:NCommon Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.ATNoneAttack requirements: No additional deployment or execution condition is required.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.VCNoneVulnerable-system confidentiality: No direct loss is represented by this metric.VIHighVulnerable-system integrity: A successful attack can cause a major loss.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
- snipe-it: 8.6.3 < 8.7.0
- Fixed
- snipe-it: 8.7.0
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
Official vendor articles1 stored document
Linked articles are downloaded and versioned as source evidence. A CVE mention or approved update relationship does not, by itself, verify a fix for every product branch.
- Consumable Inventory Over-allocation Through Concurrent Checkout Requests · Advisory · grokability/snipe-it · GitHub →Original publisher ↗Searchable text snapshot · Captured 27 Sep 2026grokability / snipe-it Public Uh oh! There was an error while loading. Please reload this page . Notifications You must be signed in to change notification settings Fork 4k Star 15k Code Issues 850 Pull requests 74 Discussions Actions Projects Security and quality 85 Insights Additional navigation opti
04
Evidence and provenance
Published 9 Sept 2026 · Last source change 9 Sept 2026, 14:18 UTC · CWE-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-09-10
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-74943
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
- ENISA EUVD mappingEUVD-2026-74943 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-74943"}
- Vendor guidanceAuthoritative vendor guidance changed: added patch: github.com/f71806b1e0efbd3bc2b6be61994ad2a5d5d6c206; added remediation: github.com/f71806b1e0efbd3bc2b6be61994ad2a5d5d6c206; removed remediation: github.com/GHSA-x4g2-87xc-m5jm; 1 further additions.github.com ↗
- Before
- remediation: github.com/GHSA-x4g2-87xc-m5jm
- After
- patch: github.com/f71806b1e0efbd3bc2b6be61994ad2a5d5d6c206 · remediation: github.com/f71806b1e0efbd3bc2b6be61994ad2a5d5d6c206 · vendor advisory: github.com/GHSA-x4g2-87xc-m5jm
- Affected versionsThe structured affected or fixed version information changed.CNA ↗
- Before
- 8.6.3 < 8.7.0 · Fixed: 8.7.0
- After
- snipe-it: 8.6.3 < 8.7.0 · Fixed: snipe-it: 8.7.0
- Public exploit evidencePublic exploit evidence changed from Public exploit reference to Public exploit reference.github.com ↗
- Before
- Public exploit reference
- After
- Public exploit reference
- Public exploit evidencePublic exploit evidence changed from No public exploit to Public exploit reference.CVE.org ↗
- Before
- No public exploit
- After
- Public exploit reference
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
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.