Malicious PDF — malware analysis report

Static analysis result for SHA-256 73dc608f47f3e2ae…

MALICIOUS

PDF

81.1 KB Created: 2021-09-16 17:50:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 078b1072c75780867a092a9efc4ff5e1 SHA-1: 1b057acda088d40f3d82555a31d88fb03711c515 SHA-256: 73dc608f47f3e2aee4869b05218fe08c01f0a39d6295f21fbc29a59d59989f03
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised or disposable domains, indicating a link farm designed to lure users to potentially malicious sites. ClamAV and ML classifiers also flagged this PDF as malicious, specifically identifying it as a phishing or trojan variant. The presence of numerous external URIs and link farm characteristics strongly suggests an attempt to redirect users for malicious purposes.

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 http://rsst77.ru/upload/files/95848197384.pdf
    • http://kommunikator.nu/demo/userfiles/file///37420357285.pdf
    • https://ever-progress.com/upload/files/sopuwubitaxupeso.pdf
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/161389d8c99794---1438104932.pdf
    • http://stavo-bazar.cz/userfiles/file/tibapiruganorofezuz.pdf
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/a792eb14322ecd38713312e9b7caff3b/nazodaku.pdf
    • http://e-motyle.natura2000.pl/imgturysta/files/fofibixapopuzesisusutu.pdf
    • http://pxmonastery.org/CKEdit/upload/files/31891082466.pdf
    • https://www.syria-report.com/sites/all/libraries/ckfinder/userfiles/files/xixulibiranemawogol.pdf
    • http://gallery4walls.com/upload/editer/file/14372956700.pdf
    • http://www.pattyn360.com/upload/forum/files/zaxufemukujalenerabofu.pdf
    • http://capthepcongtrinh.com/uploads/news/files/17874657848.pdf
    • http://limuzine.md/userfiles/file/pexovikesipiduguxova.pdf
    • https://torbay.ru/images/uploads/file/84021450968.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/b53e2evb5vd28gpqls1soquepq/girafe.pdf
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/le98ieknoed4ulfpbb512dcjl1/48317671208.pdf
    • https://vitanov.rs/files/11871575698.pdf
    • http://modaxch.com/userfiles/files/92666643185.pdf
    • http://interface-referencement.com/userfiles/file/2263335081.pdf
    • http://efuturesthai.com/uploads/file/sotuxuguvemunene.pdf
    • http://boxerdapolenta.com/cmsimple/images/file/27712015170.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613a2bb8aa9b2---metimaxanufilezidi.pdf
    • http://liga-stf.ru/i/upload/files/44111493782.pdf
    • http://csc021.com/userfiles/file/20210904134940_ms0gnr.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=hyperion+supreme+apk
    • 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_off0000d6dc.bin
2ceefbc3f8df14d5b08f12f1ff4fd6a864dd7af8d1e7f967d3ab691368e2539e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6DC 10564 bytes
font_01_sfnt_off0000eeea.bin
0ded772d9e62330f0a17bddde97c81c97a4b1a842b18b1beaeb4f0cc2732cf75
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEEA 18144 bytes
font_02_sfnt_off00011e96.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E96 16792 bytes