TMS7: Session Fixation
CVE-2026-71302 is a high-severity session fixation vulnerability in TMS7 from Toptech Systems, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected TMS7 versions: 7.6.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.29% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of TMS7 you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Toptech Systems | TMS7 | 7.6.3 | Not stated |
| Toptech Systems | TopHAT | 7.6.3 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:L. Scored by CNA (hq.dhs.gov).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 7.5 | High | CNA (hq.dhs.gov) |
| CVSS 3.1 | 7.1 | High | CNA (hq.dhs.gov) |
Official description
The application accepts user-supplied session identifiers and does not regenerate the session ID after authentication. This allows an attacker to predefine a session ID and reuse it after victim authentication, resulting in session takeover.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Session Fixation
Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.
How developers prevent this class of flaw
- Invalidate any existing session identifiers prior to authorizing a new user session.
- For platforms such as ASP that do not generate new values for sessionid cookies, utilize a secondary cookie. In this approach, set a secondary cookie on the user's browser to a random value and set a session variable to the same value. If the session variable and the cookie value ever don't match, invalidate the session, and force the user to log on again.
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in TMS7
- 9.0 Critical severity
- 9.1 Critical severity
- 9.0 Critical severity
- 9.0 Critical severity
Recent Session Fixation vulnerabilities
- 9.8 Critical severity
- 7.4 High severity
- 8.1 High severity
- 8.8 High severity
- 8.8 High severity
- 7.4 High severity
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