Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b8edfb8bdc6247a…

MALICIOUS

PDF

69.8 KB Created: 2021-09-28 09:47:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: c030c52107a2a6e95f774f59bf535798 SHA-1: c000c647cb4702492095d511be9a628ea159a2ef SHA-256: 7b8edfb8bdc6247afcc4b6b47ddc42d1b7b317e6eb7e79130510bfb00d749a30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs pointing to potentially compromised WordPress sites and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate a deliberate effort to create a deceptive web presence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://crewmak.ru/uplcv?utm_term=ps2+games+highly+compressed+10mb PDF link annotation
    • http://nirmalamathachurch.org/cms_uploads/image/file/63895854917.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/bakurulagatumorubokapiwu.pdfIn PDF document text
    • http://saaretravel.ee/images/file/libopewimijaraxibinif.pdfIn PDF document text
    • http://jn-zhsc.com/upload/78299894710.pdfIn PDF document text
    • http://anindecor.pl/files/file/gudepatetavulojenejara.pdfIn PDF document text
    • https://amoslodge10.org/ckfinder/userfiles/files/14333205225.pdfIn PDF document text
    • http://refpecsbelvaros.hu/kepek/files/zimov.pdfIn PDF document text
    • http://dyneco.kr/userData/board/file/jeboxupavipisiwakuv.pdfIn PDF document text
    • http://puisan.ru/uploads/file/befupe.pdfIn PDF document text
    • http://synowka.pl/galeria/file/kifokavarupuwike.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134289d3508f---vaputel.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/89545303442.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/sizazurutadepo.pdfIn PDF document text
    • https://nurea.se/currency/userfiles/file/fotusesogefojudesez.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/xukutifadotafaxodudej.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-9-23/20210923101711683353.pdfIn PDF document text
    • http://countryclaim.cz/userfiles/file/dabanotopidi.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/49479110290.pdfIn PDF document text
    • http://jayeonrak.com/upfile_editor/2021/files/xebuka.pdfIn PDF document text
    • https://mashura.co/userfiles/files/76638918787.pdfIn PDF document text
    • http://showpelec.com/data/file/20210926_015155_947.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/1584b29fd2bd2998a620ae7c7c099ef0/69652815444.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143da8b9ac4b---80597573863.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/vixufonugorinepodajom.pdfIn PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/zodolovil.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_off0000b117.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB117 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c929.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC929 15140 bytes
SHA-256: 5a54a134621f69568978fa5c20c77a9661340d9e6d44ffe8bdf4ed6f519ceefe
font_02_sfnt_off0000ef84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF84 11308 bytes
SHA-256: 783b65cc5e3eae6983234edada46de36b924056d744e8558777bd8caf5a0f254