Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f8490dfea90f6ff…

MALICIOUS

PDF

74.2 KB Created: 2021-05-24 04:54:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3dfd3bea681a220a8102acda8bdc2fd6 SHA-1: 93a450e616469305108c151b63c7999a77769f94 SHA-256: 8f8490dfea90f6fff25c987a5cd17d0f29cf87b4d6eaff87036150db5802a013
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the presence of numerous embedded URLs and the heuristic findings point towards a phishing lure designed to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://coffee33.ru/archive/file/kiposunufuxif.pdf
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16085e0ce7291a---84082543734.pdf
    • http://alliusie.com/userfiles/file/pupobelibetevupenuraweki.pdf
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/n6n7cld3hj3s95qh1tqsuik0h7/rajerokiwenodozinuv.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/e98209a596cd8612f0075ecb37b870b2/tanorid.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608633165e5f3---dupowudugiwudezesevorawa.pdf
    • http://ohappy.org/userData/board/file/jobijuzuxudabokiji.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/644ef7bcf8b70ed52464974d0485dc81/31744924868.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7442462108---11416362175.pdf
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160765cf8af4a0---56980545372.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160942554cbe67---fovefinapojetufome.pdf
    • https://medtek.vn/storage/file/27722632440.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074221f72007---popikisix.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1609b98846f9c8---50451582741.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/56e6ab1d24698219a895abba43fdf30e/ligabeluborofaparisu.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608fed67eb584---18268617385.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=bsc+physics+handwritten+notes+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d74b.bin
ff2431002e80a39ddee5c9f677729072dbad3a6e15b7391025cf25195c952d44
pdf-font-stream PDF embedded font (sfnt) at offset 0xD74B 5244 bytes
font_01_sfnt_off0000e922.bin
9c3a4efa037923c6b5562289e2bb7544c86453c36d0445b1169edf5f91f22506
pdf-font-stream PDF embedded font (sfnt) at offset 0xE922 10728 bytes
font_02_sfnt_off00010d97.bin
cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D97 4324 bytes