Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2859df9d084ed69…

MALICIOUS

PDF

68.3 KB Created: 2021-09-29 02:11:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 9941040f110a553ba3ec34f7b58dcf9d SHA-1: 8d54fd66c923f8d48683511f785076033dba80bd SHA-256: b2859df9d084ed69dfe0e0eb5eb94cad5702edcb4f9b840d43f11acbd7dc64c1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution via these links. The embedded JavaScript is likely used to further obfuscate the malicious links or initiate a download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=spivak+calculus+pdf PDF link annotation
    • http://sangiorgioautoservizi.com/userfiles/files/xemuxupinoketa.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/04e4483bdbdb94bd9e3df6c3a0b71a4b/41054462523.pdfIn PDF document text
    • http://www.onlinenieuwsbriefversturen.nl/gebruikers/afbeeldingen/vefuzuzig.pdfIn PDF document text
    • http://innovad-ltd.com/userfiles/file/jerorasip.pdfIn PDF document text
    • http://oookub.ru/upload/fckeditor/file/luvufemoritinoforesebag.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/2g1efm4dge9uvhgprbf9mn6tm3/49405535442.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/4711011771.pdfIn PDF document text
    • http://biondiairsystem.it/userfiles/files/sukes.pdfIn PDF document text
    • https://attackworkoutprogram.com/app/webroot/files/ckfinder/userfiles/files/72212763964.pdfIn PDF document text
    • http://pallenberg-busreisen.de/uploads/files/ropokuror.pdfIn PDF document text
    • http://exms.fr/sites/default/files/file/83060493687.pdfIn PDF document text
    • http://ventiliatoriai.lt/js/ckfinder/userfiles/files/34454873715.pdfIn PDF document text
    • http://xn--2-140-swe8h.xn--p1ai/files/nunadejegidevawiludafesi.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/okepivurere.pdfIn PDF document text
    • https://onthespothousing.com/userfiles/file/19369791092.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/vobebi.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5d604a991---suxozogodi.pdfIn PDF document text
    • http://elektro-galerie-hamburg.de/userfiles/file/23621487869.pdfIn PDF document text
    • http://tainanrup.longi.tw/uploadfiles/files/20210904_012244_9667.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff867bb096---29726917931.pdfIn PDF document text
    • http://bloomx.com/sites/all/sites/bloomx.com/files/64858523598.pdfIn PDF document text
    • 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_off0000ac76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c48d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC48D 10392 bytes
SHA-256: 0953b8532a286345527c200c1378c78fad10f653f915bb4ab0ae1a58be018093
font_02_sfnt_off0000dc2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2C 15920 bytes
SHA-256: 302c40993fe60e0c8343a80d703768b21334de0b80000897878781e7a5426027