Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a993fc4254db286…

MALICIOUS

PDF

87.9 KB Created: 2021-06-29 01:32:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8797b4f4af38c39592a7ba830253b9c1 SHA-1: 14d454063b26c796cba80c941b39bbc8b62c4076 SHA-256: 4a993fc4254db28642d524c134f545626ce9a4534877ad0d6aeb84b14d0310d6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, likely to distribute further malicious content or phish users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests an attempt to manipulate search engine results for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://ketchas.ru/uplcv?utm_term=cricinstant+live+streaming+download
    • https://mszukam.pl/dat//file/judidogezimupidin.pdf
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071dce655725---68263971679.pdf
    • http://willbramephotography.com/20306510093.pdf
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4c3e9aac1d---kemapawesamuxebaduwani.pdf
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/23fb2818bdc1a923330f6fdede9756de/kuvefis.pdf
    • http://slhs1958.com/clients/18590/File/pifebi.pdf
    • http://westtech1963.com/clients/d/d4/d4250bc21dcbbf02d7f9bc68df143add/File/turem.pdf
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/03161fc996ddab56bb290af46428bd0e/62047840896.pdf
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/slaoncrj6cn4mta7dkge9k0rrn/wosijojawodorojo.pdf
    • http://debden.org/userfiles/file/pofibojomowejezibagarapex.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1e2793311---tesuwuno.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/0a4657eff352200ccd1347c5317e2b15/32121953593.pdf
    • http://at2apigroup3.com/contents//files/voforuwuwuwegu.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c5130431a5d---welulilufavepel.pdf
    • http://soles2walk.cz/data/file/65281599739.pdf
    • http://hyundailed.com/upload/editor/file/58380545256.pdf
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8f48ec216---37759813789.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607be04cbd522---12247405881.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1b84d4efd---zexenunipasarupivedawarug.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/ovq8ba67cdvneaoq6t0ge7q697/baguzuvijegatixa.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/0bsrdditkdk6jb2401282vhgq6/53505901340.pdf
    • http://morethancars.nl/uploads/edytor/file/85041891022.pdf
    • http://anhuicrew.com/upload_fck/file/2021-5-6/20210506042818764764.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5fa.bin
b93f787ced24acd770ac931d671091bfa5292decd8839d9863ca7d83ca89a262
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FA 16696 bytes
font_01_sfnt_off00012166.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12166 16792 bytes
font_02_sfnt_off0001397d.bin
1649c464234fb2dca3cb06a349b4dd47028e7d3b43a44e3ae05f2649b0574b67
pdf-font-stream PDF embedded font (sfnt) at offset 0x1397D 10896 bytes