Malicious PDF — malware analysis report

Static analysis result for SHA-256 661f7c58c534e7fd…

MALICIOUS

PDF

78.3 KB Created: 2021-06-29 00:48:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 658f596c83adf1a44b6bc1f85198543a SHA-1: d181c1d2185bcb442c971d633649f7aa24d0c2fe SHA-256: 661f7c58c534e7fdc93c33c01cd5fcc11dbad43ba1fb9e6300a9cbd3f219e267
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely intended to trick users into downloading a malicious payload. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the structure and URL findings suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608adaba33f1d---99420142265.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/860i1uhp6gbpi954hqohkdsjk9/98810388786.pdf
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/07fa309500ebee0e61356e1fece596bd/24761955380.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/01818f5597a8521d0830b18d6d3cd422/75518007890.pdf
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb35f9cbd4---27344002701.pdf
    • http://recrute.fr/files/files/23372798478.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b6d7b5c066e---sonatudiparonafome.pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607483eb50be2---71388792299.pdf
    • http://rudolphalexander.com/uploads/files/27247555890.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb7fc47d17---gakanujevodokuvi.pdf
    • http://bertrandetgastineaudesigners.com/userfiles/file/metanumarevarapeleditopu.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c01a31a22f1---33660551029.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16073ccea03f98---zunik.pdf
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160851382acaf7---78605315275.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/f4f1ca6a7629b88df70bc422ad237403/2493961101.pdf
    • http://creptiles.dk/userfiles/file/46493998355.pdf
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c56330d6ac---34742931017.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16078149aecb5b---51562257253.pdf
    • https://kasihpaham.com/contents//files/87629196751.pdf
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/4bdd85210d3863c45c0f234426e01229/12423101922.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/hu7ucanenrqfi40efqgtvjtel7/jezogil.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/hlveomb8fng0qj9rn06f2atcet/35202862083.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=medical+power+of+attorney+in+spanish
    • http://e1pl2.nazwa.pl/busy/fotki/file/fuwulufewuvowotunelax.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_off0000ccbf.bin
83dd77fb9c595ed2595a7a4d446ce82b0bd00625ae6affb2ec75173ce5540f7c
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCBF 10908 bytes
font_01_sfnt_off0000e5f8.bin
f3e1bdddeaaad5bfb99b9733a71c3dfd3401fd6b67cb8121ac8087502e1990d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F8 17644 bytes
font_02_sfnt_off000113b4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x113B4 16792 bytes