Malicious PDF — malware analysis report

Static analysis result for SHA-256 f99462e7e38ac33b…

MALICIOUS

PDF

86.0 KB Created: 2021-10-11 22:19:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 50b31703d24462563224de2a4f9a06a1 SHA-1: d653ec4f5956e0c66c8691ba1803b4baa0dc0cf1 SHA-256: f99462e7e38ac33b567d786581ecfee677ba2ef158525f099bcd64c9f11ddc2c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, many hosted on compromised websites or disposable domains, indicating a phishing or SEO poisoning attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Embedded JavaScript streams are present, which could be used to further obfuscate the malicious links or redirect the user.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pistant.ru/uplcv?utm_term=why+do+we+change+gears+in+a+manual+car PDF link annotation
    • http://olynskiconstruction.com/pics/file/puxajejezasumam.pdfIn PDF document text
    • http://boschvietnam.com/files/usersfiles/files/64431181478.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/sogabajafumogebef.pdfIn PDF document text
    • http://stowarzyszeniemalyksiaze.eu/img/upload/files/15105730390.pdfIn PDF document text
    • http://hibertek.com/image/files/20210913_225421.pdfIn PDF document text
    • http://iiiemjobs.com/FCK_Editor_Images/files/46371080246.pdfIn PDF document text
    • http://weingut-suppan.at/files/42235127307.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161384613514e4---balekixuw.pdfIn PDF document text
    • http://tofuyatogo.com/uploads/files/47161088897.pdfIn PDF document text
    • http://easyliveconstruction.com/ci/userfiles/files/93250787505.pdfIn PDF document text
    • https://dunakanyarfesto.hu/ckfinder/userfiles/files/zopilenadomorutebebo.pdfIn PDF document text
    • https://euro-m.si/web/dokumenti/file/xigavewokulokuzapiwez.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/d0fde83c8fec98b71b740a1b8d25cb8f/sivavazomenuneliwusuxuj.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1615973441c344---93592828947.pdfIn PDF document text
    • https://bearings.vn/images/ckeditor/files/jevejivimomebam.pdfIn PDF document text
    • https://alutat.com/data/file/dedabu.pdfIn PDF document text
    • http://www2.grupoksl.com.br/js/ckfinder/userfiles/files/77876397019.pdfIn PDF document text
    • https://worldcastlive.com/userfiles/file/nofugi.pdfIn PDF document text
    • http://kolesa.sk/files/3705006464.pdfIn PDF document text
    • http://hyundainhapkhau.net/upload/files/roremosabuwemuwevil.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/xagowaxuvebuxupamodag.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_off0000e681.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE681 19072 bytes
SHA-256: fc6828c8fe743392b1ac9add16d616c0d24961eba83c40c35be156bd9751c0b1
font_01_sfnt_off000118d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118D0 11012 bytes
SHA-256: b9a6b303dc8ab7ea94ad9802c97e2c7be1a9c54049875f58b3221581b351a375
font_02_sfnt_off00013209.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13209 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1