Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f739880def17164…

MALICIOUS

PDF

79.2 KB Created: 2021-06-17 22:08:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 81b2527b998096d2fd80ec12f843f57a SHA-1: 006708b76ad6d76a278d5a078775f7f4e56059c3 SHA-256: 3f739880def171643b86adcd8a90be815a1096eddd7a10ae7650d55d9f8fe309
196 Risk Score

Malware Insights

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

The PDF contains multiple links to external sites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm used for phishing or malware distribution. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic indicates the document likely instructs the user to open a password-protected archive, a common tactic to bypass gateway scanning. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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 http://posekatzahradu.cz/files/file/18336759053.pdf In PDF document text
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/75833bc3f4c74aaa5574f73cf949ffd6/gegixixazaximalu.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/20805910691.pdfIn PDF document text
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210522093511.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/1905e9f29e2eb488f98a0614433c2a88/45794343985.pdfIn PDF document text
    • https://store-connector.com/_upload_bilder/_filemanager/file/vibimi.pdfIn PDF document text
    • http://tachikawa-derma.biz/ckfinder/userfiles/files/19697517456.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/nnhrrj9okc4invqi6nqr80l692/77570605167.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/a5f9e5166d39c12b65f78b705947e3c8/xovusonigoni.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b64947a92---tigolixizobobexetet.pdfIn PDF document text
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/8b0omdivcht1gaoi7lglglmjt8/49973786148.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/84412002270.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/l2ls520s019nn7n448c41ts85s/pikuzibuj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=minecraft+free+no+download+apkPDF link annotation
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000edab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDAB 4920 bytes
SHA-256: b615f5aa741be5f7cc2cd6f11966396a8eab07e4baa990642330f1e395adb520
font_01_sfnt_off0000fe7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE7E 10352 bytes
SHA-256: cf538070d2308c3371663afd0aea1aeacaf278637e3f6944ec608fd2f77be221
font_02_sfnt_off000121de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121DE 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2