Malicious PDF — malware analysis report

Static analysis result for SHA-256 619b43ca20fa00d5…

MALICIOUS

PDF

78.9 KB Created: 2021-09-05 01:03:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c15f8336417d438b3b930829b8517cd1 SHA-1: d183120c171512b78085e647ee5ed91755d4418f SHA-256: 619b43ca20fa00d5db4184c8353a029f4d271589090509b92b5d4c7826645172
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the structure and URL patterns are consistent with a link farm designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://cructi.ru/uplcv?utm_term=context+clues+pdf+4th+grade PDF link annotation
    • http://tz5168.com/uploadfile/image/2021/07/02/file/20210702_095615_102.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/gipomutilalez.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/31329013601.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/dd92160tdkfkbl7jglotg0ib0g/kefivegunatupozalegejulu.pdfIn PDF document text
    • https://pmms-online.com/assets/file/86929959330.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160823bbf599c7---6205995834.pdfIn PDF document text
    • https://florerialafloresta.com/ckfinder/userfiles/files/53967431586.pdfIn PDF document text
    • https://kamedia.vn/data/file/73812573721.pdfIn PDF document text
    • http://reylab.com/userfiles/file/fisijijufojinagowolo.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/cc1dcac83cd354a5b90c4a2254c247cd/puvizodozipinubanokuza.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//45875309996.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/tilefaxa.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160c9460079bd7---zapoxexisewixebevivip.pdfIn PDF document text
    • http://mastersequipments.com/ckfinder/userfiles/files/62203827018.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/b28d6d647b0d8cd55cfd46b42939c72b/fifuromujagifak.pdfIn PDF document text
    • http://kjphotocon.org/data/userfiles/files/jukoridituzipubaluzeze.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/jimejir.pdfIn PDF document text
    • http://envigest.cz/upload/file/majobunedi.pdfIn PDF document text
    • http://sequoia60.com/clients/875776/File/41944382237.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/giwebotefugekeg.pdfIn PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/fusafema.pdfIn PDF document text
    • http://feg.vn/uploads/files/volanisoliwepob.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/86247104916.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/ut4fb52o3f4jti97kd7ohinja0/60976194868.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094bb275a85c---97000180628.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_off0000d178.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD178 16528 bytes
SHA-256: d284153130b96c194931479ab172e9b229e0667f0be7964e2aeacae67ac583ee
font_01_sfnt_off0000fc03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC03 11120 bytes
SHA-256: 8a136e82526996802e6682665d007ebade67ceabc2600ca7a0255890426e2e6b
font_02_sfnt_off000115d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1