Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f733173b17cd4e8…

MALICIOUS

PDF

71.6 KB Created: 2021-09-20 08:07:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a8db74c311b6fcb44d7144943d487cfe SHA-1: 82ebe16db77f49f88fdbe198cedab4f8a6b12b68 SHA-256: 3f733173b17cd4e8e19397d762dbdd4e715b2d110bc71cfc56e19c556d1fcdcf
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the heuristic firings and URL analysis point to a malicious link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://archism.ru/uplcv?utm_term=tweaked+pokemon+go+android
    • http://scuderieverdina.it/scuderia/userfiles/file/lepavikikakiwa.pdf
    • https://aordonez.com/images/contenidos/files/76133453856.pdf
    • http://eis-pieschel.de/UserFiles/File/27273712269.pdf
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210911_CF1B86C6440260A9.pdf
    • http://podarox.ru/public/files/21766161771.pdf
    • http://nocleginaplus.pl/uploads/userfiles/files/soges.pdf
    • http://drukarnia-warszawa.pl/pliki/file/wulolawug.pdf
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/wopezexatixe.pdf
    • https://larustt.com/upload/ckfinder/files/31949275263.pdf
    • http://gorsilawfirm.com/userfiles/file/17993605766.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161333cd86951f---mezojedifasuzotokidukiwir.pdf
    • http://traktor-tv.de/sites/default/files/file/risabedigesipezoxugo.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/21fb3004c8c2b15a98a9a8e0abba3849/96729830057.pdf
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/af6e3768948c2d1100aac8de9e78d5a9/9554599960.pdf
    • https://inprovitecuador.com/ckfinder/userfiles/files/40948363906.pdf
    • http://statsale.com/data/upload/ck/files/fawojijonexowevive.pdf
    • http://webspace.mysdam.net/images/newsletter/files/najovipurusajamatem.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/56b63gqfu09rp78romtato530d/meromunovukukuludaxuweto.pdf
    • http://siamsankyo.com/Uploads/file/79131902244.pdf
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/4d3u8i4qru8krh3iq1a7tleec5/sivisolag.pdf
    • http://kassa.pl/userfiles/file/26066249030.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613846d2b7dd4---13780343433.pdf
    • https://marbeyoyun.com/calisma2/files/uploads/zoniraluwepe.pdf
    • http://exteractif.fr/pictures/2/80130160789.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_off0000b6e8.bin
a2651748fa15a6ee851713f8f5e5219c8b0ddf9756f66a53c9caed1f695fd572
pdf-font-stream PDF embedded font (sfnt) at offset 0xB6E8 10564 bytes
font_01_sfnt_off0000cec2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEC2 16792 bytes
font_02_sfnt_off0000e6d4.bin
98a9d78be19c2dc6fa2081f50ee4cc4790518505b821b263b929163393a0c1ad
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6D4 16456 bytes