Malicious PDF — malware analysis report

Static analysis result for SHA-256 e52a65cd4e1ef3b7…

MALICIOUS

PDF

66.5 KB Created: 2021-05-09 22:46:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: ff175e275d8da6b5865d66fa5b38bdfc SHA-1: a1791ffb1ce74bcd1b80394aea25feece9820bff SHA-256: e52a65cd4e1ef3b74a2f18935093e48e17d718f117d9ea8d1d50757e2d6af677
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

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 0.9994

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://oniceh.ru/uplcv?utm_term=blank+space+sheet+music+piano+free PDF link annotation
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b64890086---zuluz.pdfIn PDF document text
    • http://asupuro.com/user_data/image//file/31091249184.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/b98cf0bf179b0fc86832c6b251070991/rikubedov.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d7c1366522---90114332712.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16090174125d94---18917779867.pdfIn PDF document text
    • https://www.propertyadvisersaustralia.com/wp-content/plugins/super-forms/uploads/php/files/c81b7e48090e34867813951191153fa3/86954841470.pdfIn PDF document text
    • http://aplus.to/userfiles/file/rarogozisakobabe.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/2a462088ccb89cc05266fb70339141d0/628917491.pdfIn PDF document text
    • http://maychamsocda.vn/images/userfiles/file/zigivefuboka.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a2407c73f---zimajigenagofa.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607662ab4846f---ruvapijo.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/28c4c46b2ef9a58d5756935bbe846f4a/lemenosep.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/40950cb350eee1b51c6c0b4efd6fa8be/lonajotawolijugazedalowub.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/126033cabef87815d5c95460d74397a6/sobipuki.pdfIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD113 5368 bytes
SHA-256: fda9c33cf780157c93ac2e742e6ccf08c7643ffc45e320d50b761d7dc284ffb3
font_01_sfnt_off0000e32e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE32E 9792 bytes
SHA-256: 74458cc6150c5f33d20b35d24889a4cf5eeb47fd1646b23c86ca42aa024f8cd5