Malicious PDF — malware analysis report

Static analysis result for SHA-256 a28999ad1356bfd7…

MALICIOUS

PDF

79.6 KB Created: 2021-09-09 15:55:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 22f186ec627b1c303043db0387ed59fa SHA-1: 27390377f833bd417053f38ed55bef7a446692e2 SHA-256: a28999ad1356bfd7dd8b884e20a5144c8e1f9f200c63a227db8e0cf689378375
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was identified as malicious by a ML classifier and ClamAV, specifically flagged as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable domains. The primary attack pattern involves luring users to click these links, which likely lead to phishing sites or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://chongthamphucthang.com/images/news/files/63883472579.pdf In PDF document text
    • https://sport-jicin.cz/dokumenty/52333973303.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/31665563313.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/robufoneriwixoxunive.pdfIn PDF document text
    • http://taispacedesign.com/upload/files/jinusoxol.pdfIn PDF document text
    • http://sanga.asia/userData/board/file/bulowajuwopidixizumapod.pdfIn PDF document text
    • https://tmtteks.com/files/dojopunexuwinedewesa.pdfIn PDF document text
    • https://triatlonshop.cz/userfiles/file/66598572355.pdfIn PDF document text
    • http://vejwun.cz/images/dinivibumiwivezitilo.pdfIn PDF document text
    • http://tatnhapkhau.com/ckfinder/userfiles/files/loxofajet.pdfIn PDF document text
    • http://rigdrilling.org/userfiles/file/betomarawokanujapofax.pdfIn PDF document text
    • https://lecormier-menuiserie.com/www/upload/files/31809882297.pdfIn PDF document text
    • http://thelonerangerfanclub.com/ckfinder/userfiles/files/werelabejopaverenobaze.pdfIn PDF document text
    • http://rpsbchamber.org/editorData/file/37936426679.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/46639804693.pdfIn PDF document text
    • http://capriololaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kawuzifixiwepagiloman.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161326755017ee---lovudibizeviro.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/sumefobo.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5408e547222021d40d2421c9d5b529a7/76046260601.pdfIn PDF document text
    • https://pnp-studio.com/fckeditorfiles/file/47229189057.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/67493983118.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd1681e5eb---jupipetusa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+does+a+firestick+connect+to+tvPDF 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_off0000d375.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD375 10656 bytes
SHA-256: d2d826b580488e3ecfbe947b14c3fd9c8b233da3c3364dd3ca58e9ead6b2b69e
font_01_sfnt_off0000ec0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001041e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1041E 17396 bytes
SHA-256: b5a04d869ab3889527440434b2c3b7ac6f5591105b34159dbde21ba3a9227ed2