Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fd21530ba48dd4f…

MALICIOUS

PDF

70.3 KB Created: 2021-02-18 10:27:55 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f6fdc5e7d3cf122e3402acb1d887d8cb SHA-1: 2a62c343e889f34129eb63211c34747056e9a18c SHA-256: 5fd21530ba48dd4f7fe4fab1a3795d36d4c293a9c35695c221d28f67f5e64c8a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, indicative of a link farm or SEO manipulation tactic. The presence of a 'download button' heuristic further suggests a deceptive user interaction. ClamAV detection and ML classification confirm the malicious nature of the file, likely used to distribute further malicious content or engage in phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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 https://jacksth.ru/wix?keyword=angles+and+parallel+lines+worksheet+gcse
    • https://static.s123-cdn-static.com/uploads/4484623/normal_5ff69bbe6aab6.pdf
    • https://sozizupisez.weebly.com/uploads/1/3/1/8/131872239/8015b953cb0d90.pdf
    • https://cdn.sqhk.co/loxowopiv/hVKhfjf/51979630386.pdf
    • https://static.s123-cdn-static.com/uploads/4376088/normal_6002eccd0ed69.pdf
    • https://cdn.sqhk.co/tulotunofuz/L6phaL5/battle_run_endless_running_game.pdf
    • https://static.s123-cdn-static.com/uploads/4424025/normal_5fd04949d097f.pdf
    • https://xorodipilubila.weebly.com/uploads/1/3/5/3/135311864/750004ee2b.pdf
    • http://tushkanok.xyz/bajiwaketevajanowavepimo1z4sp.pdf
    • https://fegovelusilefu.weebly.com/uploads/1/3/5/3/135330230/gifewelobobeju.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/daraniwekamidir/zubalibukudawonekototusaz.pdf
    • https://s3.amazonaws.com/mamukawaxatali/19379215468.pdf
    • https://s3.amazonaws.com/rurosaveruk/17584732398.pdf
    • https://s3.amazonaws.com/gopifu/94043495051.pdf
    • https://s3.amazonaws.com/likadojivivofu/69863135382.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d6b9.bin
1a789a0787ee4d2652284019bd4d8bed3fbdd2e34afa1ee06274e28cdc6c8523
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B9 5480 bytes
font_01_sfnt_off0000e96d.bin
a925357c93baa6382c31f70cc332aef353f640d4dabcef8e2d13ee54dbf14a7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE96D 10176 bytes