Malicious PDF — malware analysis report

Static analysis result for SHA-256 77bb9276f8b8ae29…

MALICIOUS

PDF

74.6 KB Created: 2021-08-12 00:05:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 24a8f77401bd7a3b938d953c1527f157 SHA-1: 3e9353f0c9dfd6b8254b7a64b3bc76f58455ecc2 SHA-256: 77bb9276f8b8ae29ee69cebdc2b35dea937df9ef84a3535f0ae383db47bb8e3f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://chcial.ru/uplcv?utm_term=sports+head+tennis+unblocked+games+for+peasants PDF link annotation
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/fe9ntiihev2jsf33ibnvratuj2/loxupuzetevevuvelu.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/38874667069.pdfIn PDF document text
    • https://norservis.info/files/files/towupozemisaroxavobiri.pdfIn PDF document text
    • http://yaeram.com/userData/board/file/wijesegamelovej.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a47c5263b46---sonozemexegi.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c64e76bbe7f---zawududurebozip.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/7606145990.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/js9f47heoqro1lg98po1e1tmr4/wosetupikokutoz.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/60106f0eedab1358c8a7bb36ce8a51ce/4748486285.pdfIn PDF document text
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/5f6691f4bfa1e206da08ee7acb458900/nenagopur.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d945ff0440e---92442273985.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9700f20503---76777512933.pdfIn PDF document text
    • http://szalkasszorutacskok.hu/app/webroot/files/content/files/zazadirobamaw.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/tedebosavamepuno.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc4e333425---53378927146.pdfIn PDF document text
    • http://goldartline.ua/userfiles/file/36868912790.pdfIn PDF document text
    • https://mszukam.pl/dat//file/zidabu.pdfIn PDF document text
    • http://china-miyaco.com/img/file/202161631237.pdfIn PDF document text
    • http://bobmeetin.com/media/galleries/files/bijepuvemurowamaruxi.pdfIn PDF document text
    • http://tvoirostov.ru/ckfinder/userfiles/files/buvenorib.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160986de737717---76115647791.pdfIn PDF document text
    • http://hmconcretemixingplant.ru/d/files/vipenibesatere.pdfIn PDF document text
    • http://vejwun.cz/images/25957739045.pdfIn 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c306.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC306 14896 bytes
SHA-256: 086b9935a9dd2750c22d7d2330726cf73849c30c6249be902141f626f6e426ac
font_01_sfnt_off0000e8bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8BC 11476 bytes
SHA-256: b729ba4514ce724e2b228abaeed2b1836c896752d0e6351a126cd9b14aed1ce5
font_02_sfnt_off00010336.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10336 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1