Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a765ae881f5b9af…

MALICIOUS

PDF

88.0 KB Created: 2021-09-16 21:29:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0e0e665b3852fed9305b3173b6fc3da1 SHA-1: 56f16035ef1d89a1f4a4d2d41ad0eda2fd17f6c3 SHA-256: 0a765ae881f5b9afaa77d6b24ae9a10ad7d57725f4e11672eb30d172fb215e55
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://cn-daomeng.com/upload/userfiles/files/8bccdc5ff75bb9442a0ccf1dcbe3a16e.pdf In PDF document text
    • https://www.leasing.net.in/ckfinder/userfiles/files/roxelalolagidewejivuz.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/pojugazeziwerabufonel.pdfIn PDF document text
    • https://somogyplusz.hu/files/savixeruvipobekakofomar.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1614064ee0d548---24913194348.pdfIn PDF document text
    • https://chulintemple.house-well.com/CKEdit/upload/files/katejojavekopidumut.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/38b0556611f53f2226607d80f112326e/nobomut.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/73677470568.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/82619839060.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/kefogulomugas.pdfIn PDF document text
    • https://lazeo.nl/userfiles/file/62228285558.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/9e177250ef908956980b1c57fadd824b/14765742188.pdfIn PDF document text
    • http://verypool.cn/images/upload/File/8015091415.pdfIn PDF document text
    • http://aurora-c.jp/files/files/sopoba.pdfIn PDF document text
    • http://cegled.varosom.hu/userfiles/files/56204307564.pdfIn PDF document text
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/sunaxiragilanasowovajelel.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/rivovitaredebix.pdfIn PDF document text
    • https://kingwaterpure.com/ckfinder/userfiles/files/71037104418.pdfIn PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/simowikavivu.pdfIn PDF document text
    • http://vietkinggroup.com/uploads/userfiles/file/71986122347.pdfIn PDF document text
    • http://baiduvpn.com/upload/files/88470382808.pdfIn PDF document text
    • http://jobsandhi.com/uploaded_files/userfiles/files/62084580686.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=html+email+attributePDF 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_off0000f024.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF024 19220 bytes
SHA-256: 00d792aa13b828f58b4133a2d11ee4140cc25d1aada9790e2072109e7c4448aa
font_01_sfnt_off000123d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013bea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BEA 10108 bytes
SHA-256: 4a991cb6c47b9f3a5b960f6a0de130ef90b644875e814e2e27ec9333a4225ca0