Malicious PDF — malware analysis report

Static analysis result for SHA-256 670d72d31e40cd22…

MALICIOUS

PDF

80.9 KB Created: 2021-09-13 08:56:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a50898448bfab4557a475fa3d16d8a40 SHA-1: 2731670bf6526bc4f4008ea5f7fa921b48cf25cb SHA-256: 670d72d31e40cd228e53016f20af2ecd43ae125bee63c59deab94cf4ff74311e
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple PDF link farm heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://bustotoronto.com/userfiles/file/lelowax.pdf In PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/161386b788f483---lozosimokibubobikozotogak.pdfIn PDF document text
    • http://vektor28.ru/userfiles/file/44779367613.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/zopetaralegepe.pdfIn PDF document text
    • https://hilanguage-com-tw.triangle-design.com/files/juloj.pdfIn PDF document text
    • http://mos-craciun-inchiriere.ro/fckfiles/file/61980742341.pdfIn PDF document text
    • https://kermanrooz.com/img/files/5132376579.pdfIn PDF document text
    • http://emiem.pl/public/upload/ckfinder/userfiles/files/xofaz.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/jumanelevuko.pdfIn PDF document text
    • https://vibingvibes.com/userfiles/files/nomadomiw.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161396ab481e17---winujososebexivuzupatoko.pdfIn PDF document text
    • http://graczeonline.pl/userfiles/file/79298171455.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/wawekujugozunawizosidav.pdfIn PDF document text
    • http://skupka23.ru/upload/m/xaveremewinajadakif.pdfIn PDF document text
    • https://acavacecio.it/userfiles/files/tinepevejomoxuxuvaluf.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/9230918732.pdfIn PDF document text
    • http://cattaneoarchitetti.it/userfiles/files/votumanuruna.pdfIn PDF document text
    • http://we-women.de/default/files/uploads/file/83872244492.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/161357ecb1c381---voviluwa.pdfIn PDF document text
    • https://ezgoe.com/10005001208290177/ckfinder/userfiles/files/2956227159.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/tizevomoli.pdfIn PDF document text
    • http://campingwithconvenience.com/files/files/kekowupis.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=disc+image+burner+windows+7PDF link annotation
    • 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_off0000d79f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD79F 17252 bytes
SHA-256: 4c58176382c7273fae976f0f49026d88d6634fa6dfb2b36725d2f8cb3865b62e
font_01_sfnt_off000104ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011cc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC4 10948 bytes
SHA-256: 17bb0cfc1e4e4fe298ac0425e00d58a0e498784ddcd1a8b0a15d83447217c2d0