Malicious PDF — malware analysis report

Static analysis result for SHA-256 330f591031e37433…

MALICIOUS

PDF

105.8 KB Created: 2021-06-28 06:30:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: aff7437bcdb896fb7e988ae49dc0d5da SHA-1: 3e455d39da956e5c3b29b9eae9c069dc53d2fff5 SHA-256: 330f591031e37433b9d621bd687c9fc367e6e8d7693608554b111b947cf649c9
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to distribute malicious content or engage in SEO poisoning. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 5

  • 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://accounting789.com/ThImg/file/noximodixixulupoxapomiz.pdf In PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/7b5c5ab83ba6c6ac2227e72fc1f0ea78/vobowupile.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160806c8ee3091---kofukonasiro.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/77226030136.pdfIn PDF document text
    • https://fulzugaskozpont.hu/files/19819136166.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/79624814388.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/acf8379ff70b074a63db05a2c420bc4a/wimalifof.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e000dc1ad0---37833235976.pdfIn PDF document text
    • https://nestuby.com/userfiles/file/70345754121.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/i79ieasraouhclkt7u9t61gk31/raxugagawojug.pdfIn PDF document text
    • https://menlopark.com/wysiwygfiles/file/vozuzevup.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160922871a720a---88170880248.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160781234dde56---puwalojipugapoxode.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee82003a71---sugejotaloxivozebisas.pdfIn PDF document text
    • http://accronline.com/userfiles/file/pewojekomeni.pdfIn PDF document text
    • http://winfielddeli.com/ckfinder/userfiles/files/nesoxirozatebuxojaxoj.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5d012dfb1---73919265878.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080ddcea616f---75536017480.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/edab245531619e64e3dfbc8cb0685e58/14169685433.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cca72d09527---lomorixuxopes.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608b4c01cd6b1---50628928010.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160965a582ad2a---46651838389.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071bd0f0b08c---koxitisezoxazar.pdfIn PDF document text
    • http://kengosushionlineorder.com/uploads/files/1360264757.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=icse+total+english+language+class+10+solutionsPDF 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_off00013c3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C3E 17312 bytes
SHA-256: 55382e671b81932c1262f1c6fb25bac0bc71fed29d6ff116124b3efb30eb74f4
font_01_sfnt_off00016953.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16953 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001816a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1816A 10632 bytes
SHA-256: 51d36b6b3c9f6c7e172f919dcaa015966f41dec52ba1cbd088a9f94f614afc5f