Malicious PDF — malware analysis report

Static analysis result for SHA-256 61de4070e6d8d6b7…

MALICIOUS

PDF

96.0 KB Created: 2021-06-13 08:25:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 862e925593f8d08551e4febf5536b92d SHA-1: 535ba7fecf5694734ddd4bf27fd77dffeab33ee9 SHA-256: 61de4070e6d8d6b7905b69ee3d994bcafdaf464d5161f35ed56cd75ef5d23f61
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable domains, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the nature of the links and the 'link farm' heuristics strongly suggest the PDF is designed to lure users to malicious external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://archism.ru/uplcv?utm_term=infix+and+postfix+expression+in+data+structure
    • http://vds-construct.pl/userfiles/file/23465927082.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c0cf1118f36---83392866489.pdf
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/bp7jr4vliupks82d8709upgob5/86535423832.pdf
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070685f204ad---66282370803.pdf
    • https://prtl.pl/userfiles/file/99867612252.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160836113c1782---radibewodugadonokuz.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bca70ec5566---96077403724.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a1995305c58---68986751348.pdf
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/o4bcd4rfv731qft89e2oveg9u6/vupoporeliz.pdf
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/ueiaqt0q62n9r96geuoodtmtt0/mepufumigij.pdf
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/cb5f7ceb59e68fb71df1bc34233344c9/63535862293.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/tejnfk5g0pbfjieavji54fs3k6/48645728978.pdf
    • http://promocode.lu/userfiles/files/27977907273.pdf
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/2bee4338c600f909256060d009b8c261/sokavutidagu.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607714ae6ca57---motuge.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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/
    • https://savannah.gnu.org/projects/freefont/
    • http://www.gnu.org/licenses/
    • http://www.gnu.org/copyleft/gpl.html
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011245.bin
5fdc00fe12e3508a61241b5513525808259093ded51a384dc0df7476df407296
pdf-font-stream PDF embedded font (sfnt) at offset 0x11245 6872 bytes
font_01_sfnt_off00012396.bin
817d179cdfb8ce5cec1ac0c6609273768b2557f19dad4790169a25ee0f90fdb2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12396 5124 bytes
font_02_sfnt_off0001351f.bin
14649a53cff178e7325462ec95c497eb362f353f6ef591f7f10ce36cfc722cc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1351F 11720 bytes
font_03_sfnt_off00015d62.bin
da133098c8ec00180ce5fe37c74b807b143adc5860869a2f7b6211e455203b10
pdf-font-stream PDF embedded font (sfnt) at offset 0x15D62 16112 bytes