Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee8c9997bddc2071…

MALICIOUS

PDF

97.1 KB Created: 2021-09-19 23:29:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c6f06ea9e806d4d20b30e76c40e7efdc SHA-1: 09ed34f81050b5a91179754d3d6bdb82464dcbb8 SHA-256: ee8c9997bddc207160d545f1bfdb681ff841e250da77a40f7d2f99a14fd9aaa0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, many of which are embedded within the PDF structure, suggesting a phishing or redirection scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a link farm on disposable hosting, likely to obscure the true destination. No scripts were extracted, but the presence of external links points towards an attempt to lead the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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=pasay+city+hall+zip+code PDF link annotation
    • http://studiolaviano.it/userfiles/files/45587821579.pdfIn PDF document text
    • https://lanegarrett.net/userfiles/file/jowanojidejikilorulek.pdfIn PDF document text
    • https://mytekas.com/UserFiles/file/wovewamulavimotelu.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614491647c11c---tozumowiw.pdfIn PDF document text
    • https://centaur.vri.cz/docs/files/tebugedowepija.pdfIn PDF document text
    • http://www.singchai.co.th/ckfinder/userfiles/files/34410440030.pdfIn PDF document text
    • http://billsky.ee/files/file/jukatotajirani.pdfIn PDF document text
    • http://losmarinoslanzarote.com/marinarubicon/admin/file/melukafavidi.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/53884739718.pdfIn PDF document text
    • http://findmealocalpainter.com/insurazon/admin/userfiles/file/42219792811.pdfIn PDF document text
    • http://romento.com/uploaded_files/userfiles/files/narobukisotodoge.pdfIn PDF document text
    • http://chineseclothingonline.net/File/rukokuxepujakakij.pdfIn PDF document text
    • http://studiodabo.eu/userfiles/files/93258171588.pdfIn PDF document text
    • http://myphamso1.net/uploads/files/delejosamutawipa.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/zajazemugodupa.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210905_205548.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/67460888296.pdfIn PDF document text
    • http://rasmesafar.net/basefile/basefiles/64204362197.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/jizupironejilowajifamilu.pdfIn PDF document text
    • https://aashianarealty.com/file/36735786927.pdfIn PDF document text
    • http://art-lan.ru/uploads/assets/file/85193126807.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/161395400efa54---88160795501.pdfIn PDF document text
    • http://nomorecpapmachine.com/userfiles/files/6760476270.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-9-19/20210919131550576242.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_off000117ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117CE 17684 bytes
SHA-256: 9e768fff23e5a39fc2fff23511b01f6a2db145d913f6b091bdaa8540960683ba
font_01_sfnt_off00014616.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14616 10584 bytes
SHA-256: 1e2ce01fff7e5ba5341407957881421e8fc74c250c45d4a13ad72781d915dff3
font_02_sfnt_off00015e7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15E7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1