PDF malware analysis — malicious · 5b56418c1cfba58d

MALICIOUS

PDF

132.5 KB

MD5: 8ed49f88e589179338aaf92864f8f48d SHA-1: 988729e946424f4477e43032c0de3cf14f10da39 SHA-256: 5b56418c1cfba58d7cab513c421535b13fe934130b5f55e75df1d5000b3224cb

330 Risk Score

Malware Insights

MITRE ATT&CK

T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains multiple critical heuristic firings indicating exploitation of known vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) via embedded JavaScript. The JavaScript is designed to download a second-stage payload from the provided URLs. The ML classifier strongly supports a malicious verdict, and ClamAV detected shellcode in an extracted artifact.

Machine Learning

Nyx PDF Classifier malicious score 1.0000

Heuristics 9

Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927

PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659

PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992

PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV

ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
PDF JavaScript shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL

Decoded PDF JavaScript shellcode contains a hardcoded http(s) URL stored as little-endian %uXXXX Unicode escapes. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
JavaScript action low PDF_JAVASCRIPT

PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
Embedded JS stream low PDF_JS

PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
Embedded URL info EMBEDDED_URL

One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
URL http://relsd.in/x/l.php?s=printf_iex&
- http://relsd.in/x/l.php?s=email_iex&
- http://relsd.in/x/l.php?s=gicon_iex&

Extracted artifacts 3

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`javascript_obj0008_000.js` `1f6839cb578c4b2ab2d5afc650ea0a9141b52787e6f709d9c35443806d941477`	pdf-javascript-stream	PDF /JS object 8 at offset 0x1E7	2095 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 1 long base64-like blob(s).
`javascript_obj0008_001.js` `2b01a0e577963fed9982036b412b64478c90719e5612e62b755a287b682ced7a`	pdf-javascript-stream	PDF /JS object 8 at offset 0x209	135109 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 2 long base64-like blob(s).
`legacy_pdfkit_stage_000.js` `ce3579dcfde75943771b7cf05ef2cce77128b003a6630c24518f38ca83fcc8c7`	deobfuscated-js	repeated-marker hex decoded JavaScript at offset 0xA4A	14745 bytes
Detection ClamAV: Js.Exploit.Shellcode-18 Obfuscation or payload: likely Carved artifact contains 9 eval/decoder/string-building token(s).

Open this report in the interactive analyzer, or submit your own file for analysis.