Malicious PDF — malware analysis report

Static analysis result for SHA-256 b05bb95eba29d18d…

MALICIOUS

PDF

84.4 KB Created: 2021-09-22 19:11:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cd0285084478ce25978447426e9738a7 SHA-1: 96675883499a69178935db9ca2aa3d4a93536f93 SHA-256: b05bb95eba29d18d8bfbf3f4fd3458f92117b6961fd59f0492bcd9acd8e8990b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, indicating a high probability of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on potentially compromised WordPress sites. The presence of embedded URLs and the nature of the link farm suggest an attempt to redirect users to phishing or malware distribution sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://oniceh.ru/uplcv?utm_term=most+used+apps+android PDF link annotation
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/161357328d0eb1---93709991159.pdfIn PDF document text
    • http://homokkepek.hu/editor_up/22340369206.pdfIn PDF document text
    • http://consorzio-csa.it/userfiles/files/43250898303.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/jezafexizifez.pdfIn PDF document text
    • http://2016.letnifestiwal.pl/ckfinder/userfiles/files/nugar.pdfIn PDF document text
    • http://aligokdemir.com/resimler/files/78238162806.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/likovozalu.pdfIn PDF document text
    • https://redormiga.org/sites/portalin.es/files/file/jevurafobedudexifira.pdfIn PDF document text
    • http://ebd.su/UFD/7623/files/taxinibep.pdfIn PDF document text
    • https://artistprasanna.com/userfiles/file/xozopurigetu.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/vesibolufazase.pdfIn PDF document text
    • http://csc0731.com/userfiles/file/20210919071048_r4jwwx.pdfIn PDF document text
    • https://tattica.byespresso.com/app/webroot/files/upload/files/zibasijexutiw.pdfIn PDF document text
    • https://sabunwangi.com/contents/files/meseximete.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133bfb0e9b14---zixal.pdfIn PDF document text
    • http://poltinka.ru/userfiles/file/51168745147.pdfIn PDF document text
    • https://www.smartfutureexpo.com/ckfinder/userfiles/files/21251620825.pdfIn PDF document text
    • http://cosmosimpex.com/app/webroot/ckfinder/userfiles/files/56771997031.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/mukowotivekiw.pdfIn PDF document text
    • https://haltia.mx/sii/ckfinder/userfiles/files/77659111761.pdfIn PDF document text
    • http://kraemer-duennebacke.de/files/file/97468756390.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/qboihidu67q6i38ogchmiioed0/wagafase.pdfIn PDF document text
    • https://egyseg.eu/ckfinder/userfiles/files/zajufo.pdfIn PDF document text
    • https://a-metal.e-giant.net/archive/file/files/vafuwetorot.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/kmnmt1b6952hfp7mikaognugv1/84709890125.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_off0000e614.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE614 17820 bytes
SHA-256: 79cdb1b0563085bdb38fdb14665279fcdfd43390c94ead8d7e35956bbccead6c
font_01_sfnt_off0001140c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1140C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C23 10432 bytes
SHA-256: 37565499f151ae987c124867008d8828fa7d7f4c4f12cefa2dcf651450c1a68c