Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5cfb223d6c8a5c4…

MALICIOUS

PDF

103.1 KB Created: 2021-06-28 03:49:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d058de9f5c25756cfac0ddd4b99b7a29 SHA-1: ae746982059a25efd601d88a9385d38f4c8c7cd9 SHA-256: c5cfb223d6c8a5c4e7a8cc3b8241d80ac690327dfe3b37fbf53270b88880a836
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable domains, suggesting it is used for phishing or to distribute further malware. The file's structure and the presence of multiple external URIs are consistent with a spearphishing attachment used to lure victims to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://drafthe.ru/uplcv?utm_term=ionic+channels+of+excitable+membranes+pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8102027905---xesulozudebunafexugafujob.pdf
    • http://francescofesta.it/userfiles/files/sevalazi.pdf
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/dfd6b40d1cb27d9e3538f8469ea88ff2/7908885954.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/575mnghkrtm31ko0uijkjv9jr6/88180749055.pdf
    • http://goksirkrupskimlyn.pl/img/upload/files/ferajobosujagutaradukaren.pdf
    • http://rspon.pl/images/wyswig_images/file/sugijubalibonususozijeto.pdf
    • http://hobbstownis100.com/clients/6/66/66141d04a4341350d76ae3a38785cb5a/File/12352427880.pdf
    • http://centreforeffectivecoaching.com/media/file/42092684995.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d24cef1cd71---buvagogofidinaromax.pdf
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/dipr29t6o9923ggqt4ipmvaej2/jugupiwixus.pdf
    • https://easybuildapp.com/files/uploaded/files/begarogomoguvafud.pdf
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/5jn0j994fnkaghfn1d39qvt66v/82179237357.pdf
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/nipvvi49oirjgp679moj4leq25/wutabipukepemonigozekufem.pdf
    • http://3xlove.com/uploadfile/file/80560152264.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7ab4d6392---94772904131.pdf
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/mo2n5hjk7r2ibuu37bradqa2af/17856533519.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ae21b56eb---pijajozixevopevavaxa.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16087bb71bf243---gazotizulamoladexuje.pdf
    • http://sns-russia.ru/userfiles/file/52106094775.pdf
    • http://pkynfe.net/userfiles/file/89036341675.pdf
    • https://bluetact.com/locktactyuma/userfiles/file/dozumugib.pdf
    • http://bright-mineral.com/uploadfile/file/2021060515441231.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012ef6.bin
06f997525c18e04fc397b0de26678fb23947b38e26afd820c4178fb72205f9fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EF6 17832 bytes
font_01_sfnt_off00015dd8.bin
d9fd77ae1df0a22ebdfaab1e6eb4493f7c30709d843b73e2be59f5f25dc510e7
pdf-font-stream PDF embedded font (sfnt) at offset 0x15DD8 11080 bytes
font_02_sfnt_off0001773e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1773E 16792 bytes