Malicious PDF — malware analysis report

Static analysis result for SHA-256 c909ecdd00691529…

MALICIOUS

PDF

82.4 KB Created: 2021-09-09 05:55:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: cfdf17e94d79b106c9634cdf8d9023fd SHA-1: 3ee36992dc2524c71d84b6f40f9bdd1cdfdd3610 SHA-256: c909ecdd00691529615b53fd096cda14d5cdbf117560bb61d345eef65ed85eba
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The document body is heavily obfuscated, preventing a clear understanding of its direct lure, but the overall structure points to a malicious distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://synthecinter.com/userfiles/files/nivowogapivimamoge.pdf In PDF document text
    • http://zkojicin.cz/userfiles/file/74556919562.pdfIn PDF document text
    • http://z-sinpro.com/upload/files/tisusozuketenenorajejizo.pdfIn PDF document text
    • http://sarica.com.tr/ckfinder/userfiles/files/49682198727.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/titekoju.pdfIn PDF document text
    • https://zakarpattya-tour.com/upload/lefadiwuvuluwawisuku.pdfIn PDF document text
    • http://niktid.ru/userfiles/file/50182804990.pdfIn PDF document text
    • https://mb-classic-service.de/userfiles/file/29157123379.pdfIn PDF document text
    • https://maintogelonline2.bet/contents/files/xilujupunorexozegasi.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/91072216864.pdfIn PDF document text
    • http://budgettranslation.hu/sites/default/files/file/12415831659.pdfIn PDF document text
    • https://cicadit.ro/UserFiles/file/vukakeburidiba.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/24095260623.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/2c36ac100e395c69ea0f15cdf46a09b7/19258942716.pdfIn PDF document text
    • http://kotolantopeni.cz/file/mamibuwonisokoreruv.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/vufepufiruzo.pdfIn PDF document text
    • https://apoiotelecom.com/imagens/img_fckeditor/file/25386119383.pdfIn PDF document text
    • https://apteka-wratislavia.pl/halatecza/userfiles/file/luvidorafabogakazexun.pdfIn PDF document text
    • https://olterus.org/contents/files/74077258919.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/5934813246.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210905_35A76FF8958F4E78.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/6b672552c4d7473298af7ab96bdb8b96/93300658559.pdfIn PDF document text
    • http://nensi.si/upload/file/97105659142.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=best+offline+android+games+of+all+timePDF 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_off0000def8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF8 17060 bytes
SHA-256: 41cf413c018ce7184254e13bd6de3954a11ac468c107f37da5d40cac5db2fe6e
font_01_sfnt_off00010b0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0E 10752 bytes
SHA-256: 7a36a61f120464e3c502f3d85450a662f8811902d78804dd5460a362656851c3
font_02_sfnt_off0001238b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1238B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1