Malicious PDF — malware analysis report

Static analysis result for SHA-256 77a2199abf88d47e…

MALICIOUS

PDF

81.3 KB Created: 2021-09-19 06:55:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a4cf940c6a37c5f246e4ab48510052b0 SHA-1: 6587858ffa4f2317bcde6e184c7d34e4bc6af03d SHA-256: 77a2199abf88d47e65817d7dbfc3f78034bbdecc0955f25c7b903f0eddfe01d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The PDF structure and embedded URLs suggest it is designed to lead users to phishing or malware distribution sites, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://archism.ru/uplcv?utm_term=redmi+7+i+price+in+bangladesh PDF link annotation
    • http://hmed.vn/upload/files/46903080237.pdfIn PDF document text
    • http://www.monts.sk/upload_images/file/pibanelagobowev.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/68845248435.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/sizadupapiri.pdfIn PDF document text
    • http://contua.org/userfiles/file/93968313494.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/25801937252.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/65271965694.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e6a463a8c---disobelakakase.pdfIn PDF document text
    • http://skonasystems.com/userfiles/file/susopikofugixupokukoridij.pdfIn PDF document text
    • https://sport-jicin.cz/dokumenty/50847214015.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/kikukafotajikosimoxinot.pdfIn PDF document text
    • http://haokunchem.cn/upload/files/60602621940.pdfIn PDF document text
    • http://rts-3.ru/upload/files/72456326133.pdfIn PDF document text
    • http://traslochimontalto.it/userfiles/files/59589294800.pdfIn PDF document text
    • http://studioindelicato.com/userfiles/files/19553142950.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131a4e554202---23853469482.pdfIn PDF document text
    • http://gelikonline.ru/content/Files/mojajajenijefavul.pdfIn PDF document text
    • http://oris-am.com/editor_up/vudupufixutiziv.pdfIn PDF document text
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/rabepisisaxurodafivuj.pdfIn PDF document text
    • http://alarm.pl/userfiles/file/bawevikuxexatekufesikutut.pdfIn PDF document text
    • http://artstudiodesign.it/userfiles/files/wubixikajisukexota.pdfIn PDF document text
    • http://dsacare.com/admin/uploads/file/dubakuxidokazijosugevu.pdfIn PDF document text
    • http://mercuresamuichaweng.com/admin/file/vozaseta.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/a74b799d040d642212780890fca03176/rilalukovutamo.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_off0000d97f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD97F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f196.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF196 10980 bytes
SHA-256: 86cce3a98e5f4fc174658f843cf904523e4858cc8f1a0bfd15cf2fa98bfe6b8f
font_02_sfnt_off00010a64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A64 17164 bytes
SHA-256: 6e617198823fb5dc0ce5b9b66362f029f37f58c6221406880ccf78cc27d78274