Evidence used
- No CISA KEV confirmation is currently recorded.
- Exploitation requires an existing local or physical foothold with privileges.
- EPSS is 0.15% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2023
CVE-2023-24477High confidence
Session Fixation in Guardian/CMC before 22.6.2
Nozomi Networks · Guardian
5.4MediumCVSS 4.0
Patch only the product branches with a verified fix
Fix availability varies by productMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Low, lowered one band.downgradedsince 20 Sep 2024
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Nozomi Networks Guardian 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.
Remediation availability differs by product scope
Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
- Siemens ProductCERT: 1 affected or under-investigation product state without a fixed product state in the same current advisory
Direct vendor intelligence
2 currentAuthoritative vendor CSAF and VEX advisories
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
NN-2023:8-01 · CSAF 2.0 · revision 6 · finalNozomi NetworksSession Fixation in Guardian/CMC before 22.6.2
The vendor explicitly identifies these products as affected by this CVE.
- Nozomi Networks Guardian <22.6.2
- Nozomi Networks CMC <22.6.2
- Summary
- In certain conditions, depending on timing and the usage of the Chrome web browser, Guardian/CMC versions before 22.6.2 do not always completely invalidate the user session upon logout. Thus an authenticated local attacker may gain acces to the original user's session.
- Remediation
- Upgrade to v22.6.2, v23.0.0 or later.
SSA-647455 · CSAF 2.0 · revision 3 · finalSiemens ProductCERTSSA-647455: Multiple Vulnerabilities in Nozomi Guardian/CMC before 22.6.2 on RUGGEDCOM APE1808 devices
The vendor explicitly identifies these products as affected by this CVE.
- RUGGEDCOM APE1808
- Summary
- In certain conditions, depending on timing and the usage of the Chrome web browser, Guardian/CMC versions before 22.6.2 do not always completely invalidate the user session upon logout. Thus an authenticated local attacker may gain acces to the original user's session.
- Remediation
- Upgrade Nozomi Guardian / CMC to V23.4.1. Contact customer support to receive patch and update information.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Fix availability varies by product01
What, why and how
In certain conditions, depending on timing and the usage of the Chrome web browser, Guardian/CMC versions before 22.6.2 do not always completely invalidate the user session upon logout. Thus an authenticated local attacker may gain acces to the original user's session.
What
In certain conditions, depending on timing and the usage of the Chrome web browser, Guardian/CMC versions before 22.6.2 do not always completely invalidate the user session upon logout. Thus an authenticated local attacker may gain acces to the original user's session.
Why
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
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
In certain conditions, depending on timing and the usage of the Chrome web browser, Guardian/CMC versions before 22.6.2 do not always completely invalidate the user session upon logout. Thus an authenticated local attacker may gain acces to the original user's session.
Why
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
An attacker operating through local access 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 None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- local access → Session Fixation → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Local
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- Passive interaction required
- Attack complexity
- High: exploitation depends on specific conditions
- Security boundary
- Not a CVSS 4.0 base metric
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-384 ↗
CWE-384: 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.
- 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:H/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/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.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.ATPresentAttack requirements: A particular deployment or execution condition must be present.PRLowPrivileges required: The attacker needs basic user-level privileges.UIPassiveUser interaction: A user must unknowingly interact with the vulnerable system.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VIHighVulnerable-system integrity: A successful attack can cause a major loss.VAHighVulnerable-system availability: A successful attack can cause a major 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. - Fix availability varies by product
- Action
- Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 9 Aug 2023 · Last source change 20 Sept 2024, 12:13 UTC · CWE-384 · Session Fixation
CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2023-28495
Product sourceVendor CSAF · Nozomi Networks
Remediation sourceVendor CSAF · Nozomi Networks
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- Affected versionsThe structured affected or fixed version information changed.Nozomi Networks ↗
- Before
- < 22.6.2 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- After
- < 22.6.2 · Fixed: Upgrade to v22.6.2, v23.0.0 or later.
- Remediation statusRemediation status changed from Awaiting fix to Patch available.Nozomi Networks ↗
- Before
- Awaiting fix
- After
- Patch available
- Vendor guidanceAuthoritative vendor guidance changed: added remediation: security.nozominetworks.com/NN-2023:8-01; removed remediation: cve.mitre.org/cvename.cgi?name=CVE-2023-24477.Nozomi Networks ↗
- Before
- remediation: cve.mitre.org/cvename.cgi?name=CVE-2023-24477
- After
- remediation: security.nozominetworks.com/NN-2023:8-01
CVE published
Fixed release recorded from official guidance
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.