Malicious PDF — malware analysis report

Static analysis result for SHA-256 604a43d813c789df…

MALICIOUS

PDF

81.9 KB Created: 2021-06-26 03:12:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1a5bdd3e7bfea2ba1d7f006eebf0aa7f SHA-1: 41f31f6fccf2515c36d2d01203868c4b3d4e6d89 SHA-256: 604a43d813c789df46f63367a677ea5f64b4066278c4311ceaca3cb071efc37a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery through these links. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://synerhu.ru/uplcv?utm_term=liter+to+tablespoon
    • http://angarakshaksecurity.com/userfiles/file/wojikunu.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d50848e1283---56905072116.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/992cm2jovjmdd8ih12on4of052/baleji.pdf
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607632ceb5494---fuzutiwufojaba.pdf
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160766653052bb---44766979591.pdf
    • http://stacjaregeneracja.pl/userfiles/file/9077484218.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c9cc6d3621f---77237625909.pdf
    • http://ksnjl.com/userfiles/files/4288300365.pdf
    • https://amitadevnani.com/userfiles/file/79195040740.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c752531b4e2---18073656013.pdf
    • http://daieimotors.com/js/upload/files/76547042269.pdf
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/71363208154.pdf
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f56aec2f5a---53936314613.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608f2bcdcb94c---36681126569.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e8e2da26e---23228585320.pdf
    • https://nutricionintravenosa.com/wp-content/plugins/super-forms/uploads/php/files/f43a92508a6cb1f33d96a531c2e9bd76/xukolivil.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16076a069892f7---10165394436.pdf
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/warutafekokumukopesusa.pdf
    • https://evboosters.com/wp-content/plugins/super-forms/uploads/php/files/c535c1b02a4d7d41b3906bf586866a1f/85727577833.pdf
    • https://soalmatematik.com/userfiles/file/jobovoxogevipomefona.pdf
    • http://cloverpark1961.com/clients/6/6a/6a73a08bb68f643008adb5efbbb44e43/File/39503860690.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_off0000dcf6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF6 16792 bytes
font_01_sfnt_off0000f508.bin
ecdb371d02f0f438fa67dfb007d71af7652a9a6df6108b00e5f1f9600f8d9b47
pdf-font-stream PDF embedded font (sfnt) at offset 0xF508 17528 bytes
font_02_sfnt_off00012229.bin
390a87f278c11b647d59d2c5f447824feb4c7e78b3f5e116a77dbd8c8e515a64
pdf-font-stream PDF embedded font (sfnt) at offset 0x12229 10344 bytes