Medium SSRF exploit reference

CVE-2026-33619 — PinchTab has Unauthenticated Blind SSRF in Task Scheduler via Unvalidated callbackUrl

PinchTab is a standalone HTTP server that gives AI agents direct control over a Chrome browser. PinchTab v0.8.3 contains a server-side request forgery issue in the optional scheduler's webhook delivery path. When a task is submitted to `POST /tasks` with a user-controlled `callbackUrl`, the v0.8.3 scheduler sends an outbound HTTP `POST` to that URL when the task reaches a terminal state. In that release, the webhook path validated only the URL scheme and did not reject loopback, private, link-local, or other non-public destinations. Because the v0.8.3 implementation also used the default HTTP client behavior, redirects were followed and the destination was not pinned to validated IPs. This allowed blind SSRF from the PinchTab server to attacker-chosen HTTP(S) targets reachable from the server. This issue is narrower than a general unauthenticated internet-facing SSRF. The scheduler is optional and off by default, and in token-protected deployments the attacker must already be able to submit tasks using the server's master API token. In PinchTab's intended deployment model, that token represents administrative control rather than a low-privilege role. Tokenless deployments lower the barrier further, but that is a separate insecure configuration state rather than impact created by the webhook bug itself. PinchTab's default deployment model is local-first and user-controlled, with loopback bind and token-based access in the recommended setup. That lowers practical risk in default use, even though it does not remove the underlying webhook issue when the scheduler is enabled and reachable. This was addressed in v0.8.4 by validating callback targets before dispatch, rejecting non-public IP ranges, pinning delivery to validated IPs, disabling redirect following, and validating `callbackUrl` during task submission.

Published Mar 26, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.4% (30-day exploitation probability)+4
Technical severity (medium)+3
CISA SSVC: exploitation "poc"+5

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.37%

ahead of 29% of scored CVEs · Oct 14, 2026

Affects

Pinchtab

CVSS base

5.5

Medium · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

Proof of concept

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

Documented patch — github.com (NIST National Vulnerability Database)
Documented mitigation — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Pinchtab Pinchtab).
Apply the fixed version or the patch documented under Remediation.
Search available logs for exploit probes matching the vulnerability class (ssrf), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Pinchtab	Pinchtab	< 0.8.4	Vulnerable	NIST National Vulnerability Database
Pinchtab	Pinchtab	version < 0.8.4	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

High

User interaction

None

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
5.5	CVSS 3.1	Medium	2.3	2.7	nvd@nist.gov via NIST National Vulnerability Database
4.1	CVSS 3.1	Medium	2.3	1.4	security-advisories@github.com via NIST National Vulnerability Database
4.1	CVSS 3.1	Medium	—	—	GitHub_M via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N (score shown at the top: nvd@nist.gov)

Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 5.5 (NVD (NIST)) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-918 · Server-Side Request Forgery (SSRF)

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.37%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Monitor outbound requests from the server to internal IPs and cloud metadata endpoints.

web/proxy/WAF logsnetwork IDS/IPSegress traffic

Timeline

What happened to this CVE, newest first.

2026
Affected products added · pinchtab/pinchtab
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
Fix documented
Oct 13, 2026 · NIST National Vulnerability Database
CVSS changed · 5.5
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Mar 26, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

3 on the record

github.com/pinchtab/pinchtab/security/advisories/GHSA-xqq2-4j46-vwp7
Exploit, Mitigation, Vendor Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database
github.com/pinchtab/pinchtab/commit/c824574c3a05073dec2f5e9c219e22ffff8de445
Patch, x_refsource_MISC, NIST National Vulnerability Database
github.com/pinchtab/pinchtab/releases/tag/v0.8.4
Release Notes, x_refsource_MISC, NIST National Vulnerability Database

Elsewhere on this site

Pinchtab
every CVE for this vendor

SSRF
same class

CWE-918
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-33620 PinchTab: API Bearer Token Exposed in URL Query Parameter via Server Logs and Intermediary Systems Mar 26, 2026
Medium CVE-2026-33621 PinchTab: Unapplied Rate Limiting Middleware Allows Unbounded Brute-Force of API Token Mar 26, 2026
High CVE-2026-33622 A PinchTab Security Policy Bypass in /wait Allows Arbitrary JavaScript Execution Mar 26, 2026
High CVE-2026-33623 PinchTab: OS Command Injection via Profile Name in Windows Cleanup Routine Enables Arbitrary Command Execution Mar 26, 2026
Low CVE-2026-33081 PinchTab has Blind SSRF via browser-side redirect bypass in /download URL validation Mar 20, 2026
High CVE-2026-30834 PinchTab: SSRF with Full Response Exfiltration via Download Handler Mar 7, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-33619 is "PinchTab has Unauthenticated Blind SSRF in Task Scheduler via Unvalidated callbackUrl", rated Medium. It affects Pinchtab (Pinchtab); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.37% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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