Malicious PDF — malware analysis report

Static analysis result for SHA-256 233f1b50afaffd7c…

MALICIOUS

PDF

94.7 KB Created: 2021-09-01 07:56:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: bf08c437a40ea090f9c1f12d19b1c476 SHA-1: 4244ba80b46eaa31007b4462ce1cbdeb367c48bd SHA-256: 233f1b50afaffd7c19aaa936bd94d07dada393cd5c5c06f46f6feea864d7fc3b
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is used for malicious redirection or SEO abuse. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://cructi.ru/uplcv?utm_term=sources+of+marketing+information+system PDF link annotation
    • https://sport-jicin.cz/dokumenty/62192974582.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/3c0494632f31490af2bcb9087f030d02/40742313961.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/64187409481.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160929e72973a8---kafikeviwaz.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609618ce56069---89741838133.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/28923308652.pdfIn PDF document text
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/lmr4vrfe006a2dqakpurnqt74f/25973985708.pdfIn PDF document text
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/kk7avscsiosl5m62udva5h5jah/fetibin.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/a2gdudh9cj0k076qaqe6ikpo1b/fazekosigupuvobigo.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160701ed50292d---lenop.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16077ed5f362c7---bododawotut.pdfIn PDF document text
    • http://besttailor.info/ckfinder/userfiles/files/57410546397.pdfIn PDF document text
    • http://wallsfamilyreunion.com/clients/876683/File/fomifemarugefejamojidobo.pdfIn PDF document text
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/0116a77d94026695fcc058eabed089fd/dogatuzinojijagipezam.pdfIn PDF document text
    • https://orcasproje.com/userfiles/file/wisoles.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/mupozofokilusamuronolaju.pdfIn PDF document text
    • http://geoman.cz/data/file/79663387739.pdfIn PDF document text
    • https://fultoys.com/userfiles/63977386620.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607346e4e25ef---sirujewamodowesazatir.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/gpgjo2r8fo82k79udbg2s1t85a/nosajisi.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/oteaav01me9dcr8063v2f589mi/13688072462.pdfIn PDF document text
    • http://conblocmanado.com/pics/file/55152204491.pdfIn 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://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_off00011031.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11031 16776 bytes
SHA-256: d4795e123f07380c170ab5822c1ff4b078303d419ea6fd834ab01bcc730d1df8
font_01_sfnt_off00013b1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B1F 11016 bytes
SHA-256: d76e1732d4e408467a9ed79b22e9210f078ce051032251f3fe545a8b831feda9
font_02_sfnt_off000154ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1