Malicious PDF — malware analysis report

Static analysis result for SHA-256 276c4e1816372ee0…

MALICIOUS

PDF

90.2 KB Created: 2021-08-15 04:38:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 58eeef97c71004cdfb01ff95dbb7efc2 SHA-1: 45fdb2350e171832b1d466fcb051eb63df9d2041 SHA-256: 276c4e1816372ee024ce1376ba1d98ba3672bfb2d93965b2a23a2c5f7b0b9599
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ClamAV and an ML classifier. It contains a large number of embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm. The primary purpose appears to be directing users to potentially malicious or phishing content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://crewmak.ru/uplcv?utm_term=atomic+structure+study+guide+answer+key PDF link annotation
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/c4755ff8d4e65a50bdaa986af1b5ac05/gabeju.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/95843500523.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc53d10d00---67762233336.pdfIn PDF document text
    • https://ayurmitra.com/files/file/kubajixagafirexago.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/ca8d7393718777ce6771bd24b57e7a98/ravitokolevulusilixagiw.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/fe6b9a0ba4bb6205cab5db934cddce2f/11496567154.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/si7qaj8q8lnrapkrqm8mt29h75/5721194727.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/12098685061.pdfIn PDF document text
    • https://usdcp.jp/user_data/userfiles/files/woloboza.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d5359ef388---gipapepuzovinosufumuteke.pdfIn PDF document text
    • http://www.mustwalge.ee/data/content/files/xejobune.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/1659729180.pdfIn PDF document text
    • http://koreaseowon.com/ckupload/files/55334904222.pdfIn PDF document text
    • http://cnkls.com/userfiles/file/1625888150.pdfIn PDF document text
    • https://twinslock.com/ckfinder/userfiles/files/tiromurituwigipenamu.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/tolotunub.pdfIn PDF document text
    • http://dzbnf.com/upload/file///milepikozaxisati.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/35870362870.pdfIn PDF document text
    • http://remaining-mc.de/userfiles/file/sezadokijepado.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/16760004411.pdfIn PDF document text
    • http://shopsuathientu.com/uploads/userfiles/file/18820972509.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/wokidoleteke.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210705041359.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_off0000fbc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBC8 11040 bytes
SHA-256: 3dac130c6433ea0580b34a6cf15a514cd048c75991d3ef4e0f815323a2e8afb0
font_01_sfnt_off00011564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11564 17052 bytes
SHA-256: 06605170535f4562c7d9964ee98116329e913f6aa075699a8bf383ae243a4775
font_02_sfnt_off00014236.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14236 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1