Malicious PDF — malware analysis report

Static analysis result for SHA-256 77a3019fbec946f7…

MALICIOUS

PDF

86.3 KB Created: 2021-07-01 13:42:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: dcc97bcbc1def0b0f7b7c4b0cf4eee64 SHA-1: ea39a7c8cb909aaa4241c2cbf089890876d52cdb SHA-256: 77a3019fbec946f73ae1dd0a10849663d9eb1f40828780f4551d3a79c5608310
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm or redirection mechanism. The presence of embedded URLs and the nature of the heuristics indicate that the PDF is likely intended to lure users to malicious sites for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://synerhu.ru/uplcv?utm_term=game+units+crossword+clue PDF link annotation
    • https://elpmarketing.ca/wp-content/plugins/super-forms/uploads/php/files/955bc22b8076ae02cc34bcb9a97f603c/panerusejipegut.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/raditexab.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/60dd38d320b5686b457a08e279319d19/87771388452.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a46e4d7468d---79644844386.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160896e77b309d---tekug.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/jesolotesadilavuwiram.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160bababc0662d---11968146991.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607592e6762bc---pevunogikosesopuz.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/fde573ef3b4a3707378741306960b5bc/87911231178.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/d24oc5bo8mo7476l2r8gvf7g10/36848340251.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/2f66fde9ca978cfcfbe3b1c2d1633baf/71053741219.pdfIn PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/18483338223.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/42328863390.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/e6q37iio16ddstuudgnbnft586/76545075114.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/xikiromefipepafazanuxix.pdfIn PDF document text
    • http://ddservice-bmw.pl/userfiles/file/94467649894.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16092ba1a94257---dedidexemalobamamubimux.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/46b04dca3e88cf818924bc4f2f988eec/dijinekibozu.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/c2c3b22f1f30a4e00d0e424a224d192b/ponad.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160852ee645bc9---40113226468.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/08258439e223b722a4d6096af53a28d2/fofuxapenulajufib.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bebbf273aa---wopapuxinipukon.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/6cb35jr9gvd2oav5hcbn9v75a4/zoluxozakekivo.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/ziratofuwisebozepusu.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_off0000eda1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA1 17436 bytes
SHA-256: 46b97548d9ce8f032e7df0f95239817affbae97f86a35fc2987ad034bc15239f
font_01_sfnt_off00011b13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B13 10756 bytes
SHA-256: 7cbe7fe5dc33cde113e9270d22261bf9b973f53f6e0cb8c47449b10dfce18ab7
font_02_sfnt_off000133dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1