Malicious PDF — malware analysis report

Static analysis result for SHA-256 12cfa400fcf09d7b…

MALICIOUS

PDF

81.5 KB Created: 2021-09-14 13:10:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 00995b111676e7fba03984736c9492fa SHA-1: fc9eb9338fcf61594f0a5f29cf217ecc5e0d8ae8 SHA-256: 12cfa400fcf09d7b72be13d8aa17920db3cd404b573da8430f56e70cd9fd46a5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO spam. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://cukiernia-waltar.pl/qcms/userfiles/file/24069535833.pdf
    • http://www.uc-kushiro.net/images/library/File/48380319145.pdf
    • http://phuongdonggolf.vn/app/webroot/uploads/files/tivomatulufatapokitana.pdf
    • http://ski-experience-japan.com/images/blog/file/85323518258.pdf
    • http://lynhuagiasi.com/Images_upload/files/kibebejaxo.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/161347b54e9842---28091704934.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f95f8eedf---tikunepatigufuxim.pdf
    • https://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/5002305225.pdf
    • http://nwatchonline.net/userfiles/file/59427410053.pdf
    • http://kleinschaden.expert/userfiles/file/puxutinasimuxupagimi.pdf
    • https://arhometutor.com/userfiles/file/dolirapufewukuxo.pdf
    • https://www.weboonline.com/ckfinder/userfiles/files/63380987389.pdf
    • http://isdoor.ru/uploads/files/retilovogegubu.pdf
    • http://cpviettin.com/upload/files/fapizubezomiwelok.pdf
    • https://pieseautocomenzi.ro/userfiles/file/sitenev.pdf
    • http://angel-conference.org/upload_fck/file/2021-9-11/20210911075928482931.pdf
    • https://ksuskalology.com/images/file/pupolaziwofexowubirezonis.pdf
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/30f542f45725fb81cc7981e314e8c1ec/64658874901.pdf
    • http://exim5.hu/_user/file/65172286311.pdf
    • http://architettotoma.it/userfiles/files/fugokap.pdf
    • http://heorungminhphat.com/luutru/files/lapugu.pdf
    • http://biomax.shop/filespath/files/20210908150019.pdf
    • http://sendedianqi.com/upload_fck/file/2021-9-13/20210913231637265718.pdf
    • http://deborahkay.com/ckfinder/userfiles/files/nuvebupugugusazuton.pdf
    • https://vidaleve.ind.br/ckfinder/userfiles/files/28854154196.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=get+fake+followers+and+likes+on+instagram
    • 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_off0000d9a8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9A8 16792 bytes
font_01_sfnt_off0000f1ba.bin
f582f71d5731a05e669e98ed8680e5ba5c5b4ec8302e58936b3c24d35ef119f5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BA 17156 bytes
font_02_sfnt_off00011e7c.bin
2522a7d2703de8f0deabef1a8c2fdc29df3cdaf4d03c61a26758dff67929e55b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E7C 10916 bytes