Malicious PDF — malware analysis report

Static analysis result for SHA-256 72831bf0b4f50983…

MALICIOUS

PDF

67.7 KB Created: 2021-06-04 22:08:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: bf71594b6c7549c05e277f603a73a4a0 SHA-1: d077528401ade1f41c56b7fbe0567ed53251df13 SHA-256: 72831bf0b4f50983341aa74fa5f6966dadbccba2e7c08c7a19f0ec66b911b26c
156 Risk Score

Malware Insights

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

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 0.9998

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://irlanc.ru/uplcv?utm_term=example+of+a+good+resume+for+a+job PDF link annotation
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160983d968a3f8---20990583955.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0a183315df---fokesozamanikojuka.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a13b8b7bbd---32437909268.pdfIn PDF document text
    • https://hasekei.jp/userfiles/file/tivumusovuxuvitipewebira.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607471af977ec---51622868538.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a25b73a12ea---19143568631.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/jenenowikezobe.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1bc50f202---zonojixanefuw.pdfIn PDF document text
    • https://anmimar.com/royal/userfiles/file/rikenanafabiwimud.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file/%5C/2021050322073788.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160707e1f24618---renubadewika.pdfIn PDF document text
    • http://avgdesign.com/userfiles/file/narugojiperofatevugen.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/160733ed410dbd---vokizesaxosomujoriwuji.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606efc6f39485---todose.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c9e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9E7 5604 bytes
SHA-256: 1af302599b7e3045d44f2605072848aca9b61c2c2442d0e7b46ab4fa94f7948a
font_01_sfnt_off0000dce6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCE6 10788 bytes
SHA-256: 810e64ed7f26a24f4e0a91a49094408035ce3af38baa383e9177208f11db8709

Open this report in the interactive analyzer, or submit your own file for analysis.