Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ac73be62af935ab…

MALICIOUS

PDF

70.2 KB Created: 2021-10-02 20:55:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 1b7262c4f4450d1c2b8a0d372048c782 SHA-1: 5d7b877c36a7f1c2bfdce1fd907cda5dc23b38cd SHA-256: 4ac73be62af935abd3f675b2a4f0977aa6c5ac04e596b08a65d58a7ec30a5c6f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It contains a link farm with numerous URLs pointing to various domains, some of which are hosted on compromised CMS uploads or disposable hosting. The presence of these links suggests an attempt to lure users to external sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://alda.pl/ckfinder/userfiles/files/mupijofiwiged.pdf In PDF document text
    • https://linhngapt.vn/upload/files/ponafugevalizomuronijorop.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/491281b51cf4f45ff1219aec7014f5ef/4976020404.pdfIn PDF document text
    • https://oasis-travel.ro/files/wojezaluxititefu.pdfIn PDF document text
    • http://ukkies.be/userfiles/file/82795192236.pdfIn PDF document text
    • http://chinazzjx.com/d/files/71340338663.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/51976040159.pdfIn PDF document text
    • http://studiolorenzoni.eu/userfiles/files/37566937466.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aec4e756bd---1765068757.pdfIn PDF document text
    • https://etravelbox.com/scgtest/team-explore/uploads/files/79387025072.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/mubapotimepuwujifuwi.pdfIn PDF document text
    • https://cr2tek.com/userfiles/Proj_Name/files/1682191950.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/fowezeromodewebof.pdfIn PDF document text
    • http://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/64808653004.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/18711508941.pdfIn PDF document text
    • http://modellszerviz.hu/userfiles/file/29915328573.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16130bf6cd438e---jadovusida.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-16/20210916110728907385.pdfIn PDF document text
    • https://unitytradecapital.com/ckfinder/userfiles/files/zamosovogumagejaxoxow.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/55444722979.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/25615984785.pdfIn PDF document text
    • http://awards.nl/img/cms/file/4393068819.pdfIn PDF document text
    • https://patriciobanados.cl/upload/file/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=examples+of+3a+mewps+include+scissor+lifts+andPDF 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_off0000b188.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB188 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c99f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC99F 11224 bytes
SHA-256: 9e9b2014c917ebad444d2b97ec4e24f115e71060dae013451c85cfcad7f09aae
font_02_sfnt_off0000e400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE400 15280 bytes
SHA-256: 92574a5d767911441bc97c5664a127cfdb7ef9b03a431959e3d1402ba8c4c057