Threats / Progress / CVE-2019-18935
CVE-2019-18935
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-09-19
Progress Telerik UI for ASP.NET AJAX vulnerability
Progress Telerik UI for ASP.NET AJAX contains a deserialization vulnerability in RadAsyncUpload that allows remote code execution on the server.
Verdict
Today item, not a backlog item.
Unauthenticated attackers can exploit unsafe deserialization of untrusted data through the RadAsyncUpload component to achieve arbitrary code execution in the w3wp.exe process context, enabling full server compromise.
CISA KEV Yes · 2021-11-034Ransomware use Flagged4EPSS 0.99737 (verify live)5Exploit Weaponized · public PoC6CVSS 9.8 (CISA)3CISA SSVC Exploitation: active · Automatable: yes · Impact: total3
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
480 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.99737 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) · Affected: Progress, Telerik UI for ASP.NET AJAX. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
Weakness (CWE)
Mapped to CWE-502 Deserialization of Untrusted Data — weakness family: Injection.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: yes · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 693 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
Public exploit available
Public exploit tooling is catalogued for this CVE (a functional/weaponized public exploit). Catalog entries: Metasploit module. We link the catalog page(s) only — no payload or code is hosted or restated here.Link, never host — the catalog page is the source; basicsecurity.net does not redistribute payloads.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious serialized object and send it to the RadAsyncUpload endpoint without authentication.
Business
The application accepts and processes untrusted input without validation, creating an entry point for attackers.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I trigger unsafe deserialization of my payload, which instantiates arbitrary .NET objects during the deserialization process.
Business
The deserialization mechanism executes attacker-controlled code during object reconstruction, bypassing application logic.
3
Lateral reach — past segmentation narrative 3
Attacker
I achieve remote code execution within the w3wp.exe process with the privileges of the application pool identity.
Business
The server is fully compromised; attackers can steal data, deploy ransomware, establish persistence, or pivot to internal systems.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05
Coverage & confidence
— what we know, and what we don’tEstablished (cited)
Coverage gaps — stated, not hidden
Disclosure & credit2
Catalogued by mitreCNA
Credited with finding itNo finder is named in the public CVE record or the scanned vendor advisory — attribution scoped to the sources checked.
Found an error? Propose a correction.
A correction is a cited counter-claim — it must cite a source,
gets reviewed by a second human, and is never auto-applied. See the
correction convention and our identity
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