Malicious PDF — malware analysis report

Static analysis result for SHA-256 353d4ee163e3357e…

MALICIOUS

PDF

76.1 KB Created: 2021-07-28 07:23:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 58d4e4afeebd49ee8946e6d7af3ea9be SHA-1: b5dfc83c0204ebad0c4d8975df59f1355039953f SHA-256: 353d4ee163e3357e0cd69912343d772bebc40649b9cf10a4e50c0088ae966207
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is often used to download and execute malicious payloads. The presence of a link farm pointing to multiple distinct hosts, some of which appear to be compromised WordPress upload directories, further indicates a phishing or malware distribution scheme. ClamAV detection as 'Pdf.Phishing.Trojan' reinforces these findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nnt52.ru/userfiles/file/vodojiwixagufoviniminawax.pdf In PDF document text
    • https://genegurumiraclehealer.comuserfiles/file/pixixenixulurejuloru.pdfIn PDF document text
    • https://iword.de/userfiles/file/26730925134.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/onj9v3dl1s4pi2fgmpiik7qnc4/81456797144.pdfIn PDF document text
    • http://hiace-yoshikawa.com/js/upload/files/63999235108.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0d7237bb29bd677641c5fc1911254d0a/mitemulisumu.pdfIn PDF document text
    • http://parejalecaros.com/adjunto/upload/fck/files/soligavodarolanowozefiju.pdfIn PDF document text
    • https://papiratisk.cz/soubory/51697613328.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/jexikikigused.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16080431a29c25---fubuxewesifukiwosel.pdfIn PDF document text
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/zojikujosun.pdfIn PDF document text
    • http://sxcec.org/userfiles/file/11585357690.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a4274dc76a---bibagosijawixotidupi.pdfIn PDF document text
    • https://www.gico.ge/ckfinder/userfiles/files/fetejisomogipijinexo.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16095cd3cabe03---vakefulazivapak.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/35f3a7d09c731bcfdfb320b83636d16f/vavadojekinakotegerinimuk.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/51b3448125d9067448e2995b38a9e501/pipewukufo.pdfIn PDF document text
    • https://parokisantolukas.org/Uploads/userfiles/files/41629767117.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/jabawalumudulasine.pdfIn PDF document text
    • http://phatnang.com/media/ftp/file/pefiwixukinexezojavabege.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/16070c4bd22278---tuluviwulomagig.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/vh3qms1gv0mq8ssfhv6mdvk827/sazubelivuwodovi.pdfIn PDF document text
    • https://dolmalatrek.com/userfiles/file/voxawiwelojoxanodarepos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=esen+yay%C4%B1nlar%C4%B1+%C3%BC%C3%A7+renk+9.s%C4%B1n%C4%B1f+matematik+soru+bankas%C4%B1+%C3%A7%C3%B6z%C3%BCmleriPDF link annotation
    • https://www.rt9.rspo.org/ckfinder/userfiles/files/77401508972.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_off0000c01d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC01D 11748 bytes
SHA-256: 28695d8cc1ecc184c9007fdafd983a8ebdd1be8d06503e3916d08b9583cd1e9c
font_01_sfnt_off0000db60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB60 17536 bytes
SHA-256: 7b8d550e43d43d320b080e586ecccdfabca4027e25b0271a829f6787443de99c
font_02_sfnt_off00010692.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10692 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1