Malicious PDF — malware analysis report

Static analysis result for SHA-256 4495c1d4742a7559…

MALICIOUS

PDF

80.9 KB Created: 2021-09-05 18:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ce6a73744cb10a7cfd98d27b961cc341 SHA-1: c28c890ec84ae46a9d188417a9d88384b838da8b SHA-256: 4495c1d4742a75594d9ea3f8d474eb917f7642e64e5f2cacc552b8ecec9cd5da
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://budaikepkeret.hu/uploads/file/14793258672.pdf In PDF document text
    • http://hitecds.com/userfiles/file/72206646586.pdfIn PDF document text
    • http://covinahigh1980.com/clients/1/14/147ee80f0cf2e08ca1b5067d21485a43/File/dezejokumanu.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160878387b118a---bemevelisabap.pdfIn PDF document text
    • http://suseefinance.com/userfiles/file/62849145867.pdfIn PDF document text
    • https://scheidungsrecht-best.de/userfiles/file/38746454124.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab0f90435b---37453030675.pdfIn PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/12249570126.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/mijusizat.pdfIn PDF document text
    • http://macphersonproperties.com/clients/876251/File/9271721389.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/dagokuzudawupofu.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae10499f324---vekuragi.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/df4bc6e64c1541bccebe1cb1ef050622/59694769584.pdfIn PDF document text
    • https://ikincielinmak.com/upload/ckfinder/files/4887340938.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210815000023.pdfIn PDF document text
    • http://bogelaipigeon.com/upload/file/80843730859.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/naledunefidetelidenus.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132b537dc12c---piwujixojusobaxofenojev.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/33534286192.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/16111b6458e738---99981347819.pdfIn PDF document text
    • https://mmszke.hu/files/file/63865799783.pdfIn PDF document text
    • http://luatsubienhoa.com/upload/ck/files/22431412947.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=adobe+pdf+reader+error+109PDF 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://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_off0000d4c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C1 19156 bytes
SHA-256: db43f4a1287ab6a74b16391b62c8ffbec3fd64c907a80af69fcd1e7e964afda7
font_01_sfnt_off0001067b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1067B 10448 bytes
SHA-256: b7ed88adc087b5043518369582e7d33732d8a67c363713cf37f65a0466be4b49
font_02_sfnt_off00011e10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1