Malicious PDF — malware analysis report

Static analysis result for SHA-256 d087c31a48af0eb3…

MALICIOUS

PDF

88.2 KB Created: 2021-07-26 01:45:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1a526245feffc86e85060228de184e90 SHA-1: 88825991cdc5ebebd5da33d895448ef720f5a236 SHA-256: d087c31a48af0eb317d409794c4c5e76c677481b0c5ccec33a8c907cd033e358
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous compromised websites, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable, but the heuristics confirm the presence of external URIs and compromised CMS upload links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • 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.
  • 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://accesoriosalmayor.com/images/userfiles/file/43794052261.pdf In PDF document text
    • http://ebbers-schilderwerken.nl/uploads/files/13249014563.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/7752917698.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/bojilixinamasabakus.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160963e6501606---zumelavupo.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/8hvdrc5b2o69p3lbe3qdht6vrn/kopodelujoxopizizoruxu.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/ubkt8igfvhevss57vaclf0nsp4/38970167165.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/u8478lc4la3t8prttumvnlp64u/31731253549.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/6eqh7ri0vv1jkj6vhrsr1fvpeq/48457210374.pdfIn PDF document text
    • http://nomaquito-travel.com/editor-images/76008928602.pdfIn PDF document text
    • http://jevades.com/aircraft/fckimages/file/1814857892.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160859ff7232f7---mituj.pdfIn PDF document text
    • https://hopadive.cz/ckfinder/userfiles/files/pukovamufobok.pdfIn PDF document text
    • http://testplanet.nl/uploads/files/fitazowiruzutojexa.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5a3c040e89---95024625533.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3f9ce74c70---52194141149.pdfIn PDF document text
    • http://citra.cl/userfiles/file/49933857199.pdfIn PDF document text
    • http://cestovni-postylka.eu/userfiles/file/nedeguguj.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/4077ba860606ce7b02f78ac85452a621/sevedefujowetuteli.pdfIn PDF document text
    • http://greenreunion.org/clients/f/fd/fd69eab1634eeea6368acebbe5d5cb0d/File/dunodukawanugisewexude.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/f5fe19158897c3bad392daa006aeb82c/22430868159.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/39844621520.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160758120a5e8b---35944183497.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=will+there+be+a+spider+man+homecoming+2PDF 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_off0000f38b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF38B 11216 bytes
SHA-256: d78e7baabb9ff45c8ed44eb7f3e2d4fd65f41cc18c50dac83f868db720590906
font_01_sfnt_off00010d3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001254f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1254F 17400 bytes
SHA-256: 654d89c80224b53f71ebf63f7fa7b9c33a1f6ca3ab3eb3717c5d2cbe57a568dd