Security readout for executives and security teams
Plain-English summary
HotCRP 3.1 contains a critical flaw where a logged-in user can abuse formulas to make the server run unintended PHP code. For organizations using HotCRP to manage conference submissions and reviews, this could expose sensitive data and disrupt the service. The issue is reported as fixed in HotCRP 3.2.
Executive priority
Treat as urgent for any organization running HotCRP 3.1. This is a remote code execution issue with potential full compromise of application data and service integrity. Prioritize upgrade and exposure review, especially for public conference sites with many user accounts.
Technical view
CVE-2026-23836 is an input validation/code generation flaw in HotCRP formulas, introduced in April 2024 in version 3.1. Inadequately sanitized formula code generation can allow arbitrary PHP execution. CVSS 3.1 is 10.0: network reachable, low complexity, low privileges required, no user interaction, changed scope, and high CIA impact.
Likely exposure
Exposure appears limited to HotCRP version 3.1 based on the provided CVE data. The attack requires a user account or other low-privileged access. Internet-facing HotCRP deployments, or deployments with broad reviewer/author account access, should be treated as higher urgency.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. The CVSS vector indicates exploitation is network-based, low complexity, requires low privileges, and needs no user interaction. Do not assume exploitation has occurred, but the impact justifies urgent action.
Researcher notes
Evidence is strong for affected version, root cause, severity, and fixed release. Public sources provided do not confirm active exploitation, exploit availability, indicators of compromise, or affected versions beyond 3.1. CWE is listed as CWE-20.
Mitigation direction
- Upgrade affected HotCRP 3.1 instances to HotCRP 3.2 or later per vendor guidance.
- Identify all HotCRP deployments, including conference-specific or temporary instances.
- Restrict HotCRP access to trusted networks until patched, where operationally feasible.
- Review the GitHub advisory and linked commits for vendor-specific remediation details.
Validation and detection
- Confirm whether any deployed HotCRP instance reports version 3.1.
- Verify patched systems are running HotCRP 3.2 or later.
- Review HotCRP account activity around formula use for unusual behavior.
- Check vendor advisory updates for additional indicators or operational guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-20: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-23836 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 10 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H3.16Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
10CriticalVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/kohler/hotcrp/security/advisories/GHSA-hpqh-j6qx-x57hCVE reference · x_refsource_CONFIRM
- https://github.com/kohler/hotcrp/commit/4674fcfbb76511072a1145dad620756fc1d4b4e9CVE reference · x_refsource_MISC
- https://github.com/kohler/hotcrp/commit/bfc7e0db15df6ed6d544a639020d2ce05a5f0834CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.