Malicious PDF — malware analysis report

Static analysis result for SHA-256 b66c60895c10d0e5…

MALICIOUS

PDF

86.4 KB Created: 2021-08-05 23:12:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 85a3bf5d69ae767f3041cc916939b1ee SHA-1: 102a9540b76d7319078d119075decc3a98cd2ac8 SHA-256: b66c60895c10d0e52bbcb82ae96612c750201f90e05ffc8f71e9353834aee7f3
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple websites hosted on compromised CMS platforms, indicated by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL targets are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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 http://ratchee.com/ckfinder/userfiles/files/futixaxejev.pdf In PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/347odk17l47da8oalg5borl6sh/71781240333.pdfIn PDF document text
    • http://fotostudiovaccari.it/userfiles/files/7721614253.pdfIn PDF document text
    • https://pfhotel.gr/ckfinder/userfiles/files/tupimewup.pdfIn PDF document text
    • http://artkulinaria.pl/sites/default/files/file/14699781154.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/7461503cc508a25a82b0269a1eaee9e0/49991430554.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/4i4k77einelob2ckqseat0mj6l/xomiwov.pdfIn PDF document text
    • https://dm288.com/slicice/file/lomawozoreguzugi.pdfIn PDF document text
    • https://avigailpekelman.com/sites/default/files/file/66582469807.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/puu5pccasjn4l5jkh4q1ggvgc0/25519664051.pdfIn PDF document text
    • https://miruyuta96.ru/admin/ckfinder/userfiles/files/ririt.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a9285623f8f---65017181068.pdfIn PDF document text
    • https://kopari.hu/files/file/mesolizowutoxupanawitojap.pdfIn PDF document text
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/m3o4fahpuguboqltgqj2brs2os/88585363431.pdfIn PDF document text
    • https://tangentemag.com/img/file/53610230814.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160753b506653c---89700176044.pdfIn PDF document text
    • https://dm288.rs/slicice/file/23782303731.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b20538a2186---kosefol.pdfIn PDF document text
    • https://nabsangram.com/userfiles/file/2833391262.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/digajoriwirupokuginuduvu.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/mufuvugazematumir.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609a111d46a25---kuluv.pdfIn PDF document text
    • http://beijingxinzhi.com/userfiles/file/20210506173327_1232510278.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce770b183f9---gegizidokovasemonu.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba0a1d59ffc---gemarutu.pdfIn PDF document text
    • http://milkexim.ru/imgeditor/file/rufuvufukuxakata.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=what+kind+of+vegetables+can+my+bearded+dragon+eatPDF 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_off0000ed77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED77 11328 bytes
SHA-256: d3f619e7605338c1ac49d9f4a957fe66ea7fb7a091c486a0eb2d5b790efe8d98
font_01_sfnt_off000107be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FD0 16852 bytes
SHA-256: 7e63ddf4ffba65de82a8951d3fdcb3b5101dd7934a9a75066b7c4bf537d28080