Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed91618bcc7ec504…

MALICIOUS

PDF

71.3 KB Created: 2021-09-30 13:27:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5116578dbfeddb9c64cfffb0e9d325ae SHA-1: 38ef7474ded6572a4fa003b2b41290a307c4617c SHA-256: ed91618bcc7ec504e7ba6b5d1ce31293d2b9b0961adf05ce4fc6425606ce49ca
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links to external PDFs hosted on a link farm, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/ed187d862f28296c4ea9b15cd3ab2fb4/gozizubosonatoje.pdf In PDF document text
    • http://styrexon.cz/userfiles/file/91463001347.pdfIn PDF document text
    • https://vibangnhadat.com/uploads/files/pogowifibege.pdfIn PDF document text
    • https://armature.ir/cache/fck_files/file/robugufaparuzusilefanas.pdfIn PDF document text
    • https://kluchar.net/klucharnet/images/file/39217422046.pdfIn PDF document text
    • http://3gr-group.com/ci/userfiles/files/84021417627.pdfIn PDF document text
    • http://ryanoomen.nl/uploadimages/files/66428806307.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/48895041832.pdfIn PDF document text
    • http://gemmacapitalgroup.com/foto/file/reravuzutupagujukezejadab.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/diwogovor.pdfIn PDF document text
    • https://vatlieutaphu.com/upload/files/nogunetogumelosu.pdfIn PDF document text
    • http://studiosiciliani.eu/userfiles/files/noxanuw.pdfIn PDF document text
    • http://tearose-kitchen.com/sites/default/files/images/imcefile/91551869667.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1614e5f2b07608---99714723472.pdfIn PDF document text
    • http://www.hgekc.com/media/userfiles/file/11900282308.pdfIn PDF document text
    • http://timebymtm.com/upload/files/majuwinuzedurinazuj.pdfIn PDF document text
    • http://marymo.ru/uploads/files/kumirizusefibokifek.pdfIn PDF document text
    • https://businesslife.com/content/files/zujanagirujedox.pdfIn PDF document text
    • https://securitydm.net/slicice/file/80353019402.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/jevexufupibazidegutexolab.pdfIn PDF document text
    • https://rovetco.com/userfiles/file/97582026211.pdfIn PDF document text
    • http://rileyillustration.com/images/agency/files/zutubifufuveba.pdfIn PDF document text
    • https://siroyensao.com/upload/files/17350650006.pdfIn PDF document text
    • https://www.kuwaitpolyurethane.com/ckfinder/userfiles/files/lixoropuzageguwo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=android+10+language+settingsPDF 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_off0000b2cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2CC 16708 bytes
SHA-256: 8e2bdd5d5029c8a64179be25c258a3274313b49bcdd9fd853cbc0523676dc0bd
font_01_sfnt_off0000dd16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD16 10676 bytes
SHA-256: 50bf2fad7518b070dd5985f1e7a0ca3c58669596cb1eecf054fd505b45ab35d5
font_02_sfnt_off0000f585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF585 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1