Malicious PDF — malware analysis report

Static analysis result for SHA-256 f57de7f1a37bcb15…

MALICIOUS

PDF

81.6 KB Created: 2021-09-20 03:00:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d004522ecf52f17442a7514fcde48d30 SHA-1: 9b5cf305a31822f573c52fc6de13569269e1b848 SHA-256: f57de7f1a37bcb15a76e20fab6f328ace1f1165ec92076b2f465c4d8e50f737d
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to potentially compromised websites and disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and does not provide clear textual lures, but the presence of multiple external URIs and the overall structure point towards a malicious link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/31ca81519c7169f89776d0a637cff2de/5155930130.pdf In PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/161384a0b6f2e5---pifedujufawogunup.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/44777832050.pdfIn PDF document text
    • https://showdetango.com/bafa/userfiles/file/34985543009.pdfIn PDF document text
    • http://savitapiti.org/ckfinder/userfiles/files/59324639289.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/21918449195.pdfIn PDF document text
    • https://riminabda.sk/userfiles/file/nixidopod.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/81510532123.pdfIn PDF document text
    • http://klenderbio.com/upload/files/veresebarob.pdfIn PDF document text
    • https://golf-tout-terrain.com/publish/page/file/sosejovis.pdfIn PDF document text
    • http://coomargroup.com/ckfinder/userfiles/files/77485493114.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/86e3a5a3d9ca9f656a52a30e15782851/35903050829.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/88e8e82ea8ecc4403e5304d9014225de/49345538514.pdfIn PDF document text
    • https://sua.vn/uploads/userfiles/file/51414628508.pdfIn PDF document text
    • https://watosaphotography.com/app/webroot/userfiles/files/20210911_094509.pdfIn PDF document text
    • http://marketingnews.fr/images/file/vomesenobivulukomanamok.pdfIn PDF document text
    • https://aiaciran.org/cache/fck_files/file/59581958504.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/rotogumapojurivuvi.pdfIn PDF document text
    • http://dostavkaturov.ru/files/file/21527079410.pdfIn PDF document text
    • https://pfhotel.gr/ckfinder/userfiles/files/39158481576.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/161449f834f98f---10652824394.pdfIn PDF document text
    • https://fiscalonline.eu/app/webroot/files/userfiles/files/34445624404.pdfIn PDF document text
    • https://wrd13.com/force/file/8859455077.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210914111237320799387.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=best+night+mode+camera+app+for+androidPDF 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_off0000d9ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9FF 17236 bytes
SHA-256: fa5bf44d76056118241e834cb154def8bba4e675d5f2c0b6180600f2536fa8ca
font_01_sfnt_off000106c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C0 11076 bytes
SHA-256: 8be865e4907fbaa1a404ea0541ab2f04215ee56e01dd2db88a8471078004307e
font_02_sfnt_off0001202d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1202D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1