Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8fa44783552ea29…

MALICIOUS

PDF

82.5 KB Created: 2021-09-20 07:50:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e70aa5567e549c990458872f8af265fe SHA-1: 0299c87ebf5f086cf3c8ccb4e85c93d558b6f140 SHA-256: f8fa44783552ea29dc7f5ea474f4b54e64a524e6e1ac316ea57e2754229a18e0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to suspicious PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the idea that the PDF is used to distribute links to other potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/6de10c8ed72d19be20bb855586cbc760/44162429694.pdf In PDF document text
    • http://crabandclaw.com/uploads/files/19195510089.pdfIn PDF document text
    • https://pilot-nav.com/ckfinder/userfiles/files/24415748488.pdfIn PDF document text
    • http://villalapinetafavignana.it/userfiles/files/jitujupekomilavubijerezi.pdfIn PDF document text
    • http://x04ydivan.ru/userfiles/file/59335838129.pdfIn PDF document text
    • http://cnokorea.com/userfiles/file/28021818712.pdfIn PDF document text
    • https://theptaynam.vn/upload/files/73391714749.pdfIn PDF document text
    • https://ndmoyun.com/calisma2/files/uploads/kamepelokejirufa.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.com/userfiles/file/89821974627.pdfIn PDF document text
    • https://trexanh.net/upload/files/56639755795.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/81686296450.pdfIn PDF document text
    • http://cappellastudio.it/userfiles/files/xogixo.pdfIn PDF document text
    • http://hmsendo.pl/uploads/editor/file/folaviferale.pdfIn PDF document text
    • https://bdata.vn/upload/files/32781089674.pdfIn PDF document text
    • http://annassteen.com/ckfinder/userfiles/files/vopekoburidemumuvab.pdfIn PDF document text
    • https://datxeninhbinh.com/data/dulieu/files/nemodetogugufojaz.pdfIn PDF document text
    • http://systemsbiology.at/uploads/assets/file/vixedewepolabogasimemek.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/77567623996.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16130814f392c3---2794890495.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/23638376659.pdfIn PDF document text
    • http://bursaceyizgelinlik.com/images_upload/files/xotisox.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/wonuvepuligakux.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/51351184965.pdfIn PDF document text
    • http://itaxabc.com/userfiles/file/20210920084634_231735971.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=jollibee%27s+game+unblockedPDF 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_off0000de6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6D 10872 bytes
SHA-256: 90b583bdbcf2e16cf24e7242309bd68bf5488072987599485f4dc149b367454d
font_01_sfnt_off0000f763.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF763 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F75 17352 bytes
SHA-256: a9e037d75f2d0d45351b95623d8bc4e47821965c0a77c714e99bce176c08035f