Malicious PDF — malware analysis report

Static analysis result for SHA-256 0bd81da64535d52d…

MALICIOUS

PDF

74.1 KB Created: 2021-05-02 19:48:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 8f46fe442bf774bacc85e4292124bcee SHA-1: b2d690d5304778eaa317f6b35e59903656dbba07 SHA-256: 0bd81da64535d52d25d4b0c0334343e364c55476af823093c5e4e6abd9a1e8ab
156 Risk Score

Malware Insights

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

This PDF file is flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The document body, though heavily obfuscated, contains references to 'Tumblr app for windows 7', suggesting a lure for users to download potentially harmful software. The numerous embedded URLs pointing to compromised CMS uploads and link farms further support a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/238ee9abdf7a28dd359c9254bbf03498/jijirivimozuboba.pdf In PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608ddeaf097f6---masosebifulafo.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/5ec85a6ba27af450dcf46ccfc5c424db/zafogevemuwo.pdfIn PDF document text
    • https://nutricionintravenosa.com/wp-content/plugins/super-forms/uploads/php/files/a917d25fa0c9cfde7fba86cc2b4a7de8/nebebigafutimadan.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bed3fc30b3---likixuxadaw.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/65braem7ro56kq218vossgcl3a/42791958005.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/3c61899682f10c0bb42ad342e3028f22/xululajupupozidiwumerif.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/a26471b33124443e5674bf816d19f5fb/98956609749.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/xoxefero.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4dd79fee3---mugotovajag.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160835fc18436d---wesifazebuvivixubifajesap.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/b7a828afc41c3e96213b5f0baf727224/59754802734.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/refaj951n9bt15pevel1ftsmn6/bewatebalowo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=tumblr+app+for+windows+7PDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e64f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE64F 5448 bytes
SHA-256: 7f3ee28e9b34f75b8073d93f9e377172756231b1b9793d7e09fe84c25a7149d3
font_01_sfnt_off0000f8d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D1 10232 bytes
SHA-256: 9da59b68b6c285f23658521f182c22603b610d72a591391b91cf472008826237