Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb8ecdc3ba13a913…

MALICIOUS

PDF

80.2 KB Created: 2021-09-19 09:54:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d4f351c908b612a6541ddf9e43986698 SHA-1: 61f70f9e3004445651e572ba08863e1a94c02026 SHA-256: fb8ecdc3ba13a9130951b32402fc3ce35511550fe0c2f481f32ee828d66bfa3b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised websites or link farms, suggesting a phishing or malware distribution scheme. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the PDF is used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://nomylo.ru/uplcv?utm_term=power+of+positive+thinking+book+in+gujarati+pdf+free+download
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/temaramedajukokefasesu.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f70e43e3cb---23131017396.pdf
    • http://pastoret.it/userfiles/files/ribakozexobigumataziwav.pdf
    • https://transturist.ba/ckeditor/ckfinder/files/files/fofufiwiroxuz.pdf
    • https://newegys.egyseg.eu/ckfinder/userfiles/files/vekiwog.pdf
    • http://inphilong.com/upload/files/roxijapimumomi.pdf
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/44291925238.pdf
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144d2460cc8a---lisijobulojuxukisiwem.pdf
    • http://modulobase.com/userfiles/file/gofaderimobosur.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/02cf05feee4a571fe6d418bc3768ab86/komikeruzokowuxani.pdf
    • http://cartonwrappingmachine.com/userfiles/file/93666583581.pdf
    • https://foulardfotografando.it/file/41066362610.pdf
    • http://musthighschool.mn/ckfinder/userfiles/files/74315151112.pdf
    • https://war-old.its.vn/new/userfiles/file/lelozuk.pdf
    • http://mwflower.com/upimagesfile///kikudimafutanovozen.pdf
    • http://bajcsidavidfoto.com/_user/file/40961466381.pdf
    • http://shrlie.com/upload_fck/file/2021-9-16/20210916000137534941.pdf
    • http://nakakinpump.kr/fckeditor/upload/file/16071770497.pdf
    • http://severstroysnab.ru/userfiles/file/91614754923.pdf
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/7582188984.pdf
    • http://styrexon.cz/userfiles/file/58030346652.pdf
    • http://topnotchimports.com/ckfinder/userfiles/files/77719917508.pdf
    • http://drsuthichai.com/userfiles/files/nojijonexavus.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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d04c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD04C 16792 bytes
font_01_sfnt_off0000e85e.bin
a5661d04fb14c589f34fa18956ec180464297c2faebc99f715e972ccddc8902d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE85E 18256 bytes
font_02_sfnt_off00011849.bin
5129f716cca642ce96b649b4a53483a54fba2604cb442fa0b4b011de613b8e97
pdf-font-stream PDF embedded font (sfnt) at offset 0x11849 11392 bytes