Malicious PDF — malware analysis report

Static analysis result for SHA-256 e87aa14921544059…

MALICIOUS

PDF

68.9 KB Created: 2021-09-07 16:12:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 01f45d618c78bcc9af5f100005a678db SHA-1: 4c61ed1d796cd46da9248e7a8b58b8883244f685 SHA-256: e87aa14921544059597571a0c1515ef9031fff0e55179a898483ca12564c7dc2
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and uses an image-based lure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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=grace+fit+uk+guide+pdf+free PDF link annotation
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/0d7b82355f74cdec7f90c0fe94388581/23045503989.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/pamema.pdfIn PDF document text
    • http://ck-tct.ru/userfiles/file/9416541633.pdfIn PDF document text
    • http://quiltingacademy.info/fckeditor/userfiles/file/59432188498.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/637266dc1c8e38ea3cf36c2301b853e6/sasirizafididajazopexoba.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/b854a84a4018643c5ee7fbef76173cf0/vedewuxivapoto.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/lefakazozidofarigigum.pdfIn PDF document text
    • http://markone-tools.com/upload/files/11662791780.pdfIn PDF document text
    • http://thucphamchucnangmy.vn/uploads/files/jepifimusopigusita.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/62005994315.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/36e4b9d435e67a197637bba0127d0da5/46536932496.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16099f8635208c---40857742675.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/nimidejenafupusaxu.pdfIn PDF document text
    • https://247hvac.ca/fabulous1/uploads/files/tokegujupulugexa.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c55a9712f2ea46cf12d869fc39aafed7/bifepaluwijolufutag.pdfIn PDF document text
    • http://granitemountainranch.net/userimages/nodezo.pdfIn PDF document text
    • http://dj-maily.com/uploads/pages/files/kitewel.pdfIn PDF document text
    • http://www.scsk12.org/policy/files/files/12836439269.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/negawopurivadus.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/sipivikuxolovanezo.pdfIn PDF document text
    • http://high-keenltd.com/userfiles/file/73657744217.pdfIn PDF document text
    • https://nhanloc.net/userfiles/file/bekitodugokinoket.pdfIn PDF document text
    • https://rentcar888.com/uploads/files/202109030747473524.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_off0000b123.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB123 14004 bytes
SHA-256: cff996ca0419acf91641f4aebb6f14ee7b2691b88178bc0b33aba5f9e4b1f7a8
font_01_sfnt_off0000d3f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC0F 10588 bytes
SHA-256: 60c2c6d646f23262908c105d2ec31b71f3ba5893c4ee58c9a13093b8d5fa9798