Malicious PDF — malware analysis report

Static analysis result for SHA-256 1251572cf88a42af…

MALICIOUS

PDF

89.7 KB Created: 2021-06-30 04:19:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: fefa5945e8c0274da19069f96294f29d SHA-1: f5c31ef392d016d3aa74cac68b4c4e6e707c3444 SHA-256: 1251572cf88a42af9d5dbb5b33be743b78d346bb105f8795ca70ca74067685e2
96 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains. The ML classifier strongly indicated maliciousness, and the presence of a link farm suggests an attempt to redirect users to potentially malicious content. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://infrive.ru/uplcv?utm_term=the+infernal+devices+clockwork+angel+pdf PDF link annotation
    • http://portaldo.eu/contenuti/upload/file/63954795370.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f178eac4b---48610123744.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///mamepudikejalaketitov.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/46hao97ugcaip4qaej1js63kfu/surumifiwuxusesifurebunim.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084df8c0c2f9---wokurixi.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/ead2dr0ebhhdh9q819mb2a67d7/13817694030.pdfIn PDF document text
    • http://ndt-tl.ru/upload/file/tididovemutigowogason.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/76267277a6120976137ad37b5bc49903/94876718026.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/fijotepuwurojutipatiwurar.pdfIn PDF document text
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/025db5e10cdd3f98c6de5581234dfd14/budebesep.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/of63pie3hpterd850gmrgslim0/92846372731.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/dovojijagonuxakitaxer.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/bc86b64a2d0e203a2ff3621af1812f21/kukamisezoviviwebekavu.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/f0a1103c0a03021b8b0dcf2c9b021252/29085416877.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/wovijaduxivi.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/ac7bf1d9e91b147e5a405e5c11c06102/35058751730.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/j89q5proi0pb1mnbkdpo2fbup4/31177434426.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7cfbd2871---rakatozonona.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a73b31a9e24---24299780223.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/73733394939.pdfIn PDF document text
    • https://stgeorgedentalcare.in/ckfinder/userfiles/files/90447160187.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/4cec30566a2221e511962ecd706192b4/90043184275.pdfIn PDF document text
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/fc91c1eadca824cf38a49a84e77f4f4e/7865776239.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_off0000fad8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAD8 17216 bytes
SHA-256: b3efbe9d5559ef5dc7d71d8480cf347edda500c65f078f508ad1b56940d2ef1f
font_01_sfnt_off000127f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127F3 11008 bytes
SHA-256: 91612913846ac47c9d3c817a5ffa723e61f4db244fc8954373b3a058443a6dd5
font_02_sfnt_off0001414e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1414E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1