Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff2cef0e3cd7d318…

MALICIOUS

PDF

79.2 KB Created: 2021-03-22 11:56:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: f925bf027fe936396be504612d977015 SHA-1: 373a058371abdd2ff17fe2820e2a240e167706c7 SHA-256: ff2cef0e3cd7d318cc5e83c1ba02f8f1146914b26fa236450210caf11820621b
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan payload. It contains a link farm with numerous external URLs, suggesting an attempt to redirect users to malicious sites. The document body, though heavily obfuscated, contains metadata related to PDF generation and a keyword search, reinforcing the lure of a PDF download. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://kuzutuzo.ru/award?keyword=acgih+2020+portugues+pdf+download PDF link annotation
    • https://visuriteja.weebly.com/uploads/1/3/5/3/135323353/ba2fdb.pdfIn PDF document text
    • https://cdn.sqhk.co/xosaletozobi/jjuLgfk/35375918118.pdfIn PDF document text
    • https://gewipilozu.weebly.com/uploads/1/3/0/7/130775211/5041885.pdfIn PDF document text
    • https://cdn.sqhk.co/disumuneriva/gebpYie/acoustic_guitar_chord_sounds_download.pdfIn PDF document text
    • https://cdn.sqhk.co/dudugetogi/1BQjchZ/53695442345.pdfIn PDF document text
    • https://cdn.sqhk.co/turanexode/gixgdjc/74030752384.pdfIn PDF document text
    • https://cdn.sqhk.co/ponajadu/T6gcja1/lavibinepolewofifuwa.pdfIn PDF document text
    • https://nipituwosaxow.weebly.com/uploads/1/3/5/3/135312928/a80f84e.pdfIn PDF document text
    • https://cdn.sqhk.co/bapisolel/Qje5rjf/football_manager_2020_touch_on_mobile.pdfIn PDF document text
    • https://cdn.sqhk.co/luginuwi/1cgeMjh/42382418212.pdfIn PDF document text
    • https://tapidokebijimub.weebly.com/uploads/1/3/4/5/134577153/41a7d90d.pdfIn PDF document text
    • https://cdn.sqhk.co/besiwowegin/QOgj2YS/dinosaur_sound_effects_mp3_free_downloads.pdfIn PDF document text
    • https://rurusoweloxefug.weebly.com/uploads/1/3/3/9/133989150/f6264e32dd2.pdfIn PDF document text
    • https://cdn.sqhk.co/jopubelo/giiaDeB/minetabefunutek.pdfIn PDF document text
    • https://cdn.sqhk.co/vefusujix/hjrRljh/homey_chores_and_allowance.pdfIn PDF document text
    • https://lofizalu.weebly.com/uploads/1/3/4/6/134601384/rukareweju.pdfIn PDF document text
    • https://cdn.sqhk.co/monazaxumol/2KSihjj/anime_wallpaper_lockscreen_anime_full_wallpaper_hd.pdfIn PDF document text
    • https://cdn.sqhk.co/letarezetap/gchdjaG/lolegafofapolad.pdfIn PDF document text
    • https://jetezoxow.weebly.com/uploads/1/3/1/3/131379231/1162576.pdfIn PDF document text
    • https://cdn.sqhk.co/sogefuluf/ajgfgcx/63586283966.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://711a90e7-97f2-4eab-8690-3003ec1e9b64.filesusr.com/ugd/a0905b_d95ae3d6675e452497455249ceb0ad6f.pdf?index=trueIn PDF document text
    • https://528f6e5c-6927-42ef-b7a5-a8f9c349750c.filesusr.com/ugd/07b979_0f2c58271ba14e87a98ca74e2bab8381.pdf?index=trueIn PDF document text
    • https://f8d82b49-d438-4da2-b906-f876cb6fe635.filesusr.com/ugd/12dc78_49bd0bb45c74409c8be52049b08d54ed.pdf?index=trueIn PDF document text
    • https://eb62986f-0112-409a-9ebe-777412bc5c19.filesusr.com/ugd/26938b_2f5285321ec845a1b7099762b9a6f755.pdf?index=trueIn PDF document text
    • https://ac402fee-74f4-49a6-b5a4-6a03c6a057de.filesusr.com/ugd/b0cd75_164164b89d9b40a0a6c3d41f87b98351.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f220.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF220 5772 bytes
SHA-256: 21588004a80baef99d6f203858984fa77fe72538faf48fbe27fcbe00d025ce91
font_01_sfnt_off000105dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105DD 12456 bytes
SHA-256: 70bb330ea674020182747b2588216c5f83748fb76086bb5a174f83a01f776366