Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a856eeb3868731a…

MALICIOUS

PDF

83.6 KB Created: 2021-09-05 17:57:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7925867ae144cccf4df58177de3a260a SHA-1: 874ee80990f89c8a5e9da2de492cf0757fc690a7 SHA-256: 9a856eeb3868731a579b185c7fbb6aa5507db437d02ac05264061e424ad7b22d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is often used to exploit vulnerabilities or redirect users. The presence of numerous external URIs, many pointing to compromised CMS upload directories or disposable hosting, strongly suggests a link farm designed to obscure the ultimate destination, likely a phishing page or malware download server. The ClamAV detection and ML classifier further confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://seasonsblinds.com/uploads/ckfinder/userfiles/files/womofilubudazafi.pdf
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/pifebewejibopewe.pdf
    • http://www.stsmcc.org/www/js/ckfinder/userfiles/files/tukip.pdf
    • http://kozhencherrymtc.org/userfiles/file/41160875578.pdf
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/160870af57496e---84460874822.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161255bfb8a252---25471170498.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/cu9j4peebv73plkgt7334l0tf7/5554335038.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab5d0dc19d2---64554382335.pdf
    • http://inimtrento.it/userfiles/files/5002331982.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee3258df8a---62422602591.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a278c7459e9---girudaveb.pdf
    • http://h-n-s.net/userfiles/file/xiruxim.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160a9701ababd2---wumemobusitezesakuruvisix.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9d27ccc9e---9881344401.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/v4f914b5g9qh14clbvap7dol0h/tepexilurivariv.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b74319197a1---pitokezopopanelofi.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/16og49m4cmnkd1mptbod8eto96/pijimedoliliposunamabawep.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c6bf9f55e74---pegedevi.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070ce8a59767---sosonofoxewuf.pdf
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/2eb9608ed1d3145df0b00aaffad29498/5143564285.pdf
    • http://papianiarch.it/userfiles/files/23306511945.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607867fb95da7---97831982628.pdf
    • http://taikenplan.jp/ckfinder/userfiles/files/67668336828.pdf
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b88115fccb---87093180440.pdf
    • http://nessium.fr/userfiles/file/67330388796.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=ranger%27s+apprentice+book+6+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_off0000e161.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE161 16792 bytes
font_01_sfnt_off0000f978.bin
a7b6be2bef0abc6fc6e47baf5c31f99258d8fd74bb3bfc4149b6d381d34e8113
pdf-font-stream PDF embedded font (sfnt) at offset 0xF978 11228 bytes
font_02_sfnt_off0001138c.bin
8b9efdd051588531cccd296dff0984bcc0ba347af401eae3b5b8606944d9b526
pdf-font-stream PDF embedded font (sfnt) at offset 0x1138C 17472 bytes