Malicious PDF — malware analysis report

Static analysis result for SHA-256 c386f501acbcc3f7…

MALICIOUS

PDF

76.0 KB Created: 2021-06-27 07:44:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4b9da1b55c4aee9bdec91d5e966daea6 SHA-1: c683c613b3ff61890eea731bf32292eaab42f2f7 SHA-256: c386f501acbcc3f791b5bdd743033c6676dafca26b1d65f45fb24a4fd1b4e760
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated a high probability of maliciousness. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting. These links likely lead to phishing pages or further malware downloads, indicating a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/380c46bf653eba8a10da6b8f640a1343/79893766875.pdf
    • https://gulfsupremesa.com/ckfinder/userfiles/files/fanitetobalak.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609a70e284743---2465022206.pdf
    • https://aduanaldelvalle.com/userfiles/file/fanojorejaxiriwisefozuxu.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a8790689d---mipigovejowujujem.pdf
    • http://mfcwestenkwartier.nl/beta/userfiles/file/sapededovoborepalurubul.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cfab6e65f94---ginowulevojiza.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082a8d89c34c---vuvaduxinabogaf.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb6cb3180a3---81100237023.pdf
    • https://balaji-technology.com/userfiles/file/80121825808.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf6469fa8e---72429953579.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/tufuzojotidi.pdf
    • https://cafesca.org/ckfinder/userfiles/files/tuvofazomasa.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1608462578d6ee---60704008706.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097e5252c2b1---70786825690.pdf
    • https://fulzugaskozpont.hu/files/74406223774.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/8e67940734ec4a9f1f5e5a7bcaaf78be/44985910711.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608139f64f8a9---62557259461.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/84be85f28ed415743122f2ef54ff7a4f/womikogunesotedarunupad.pdf
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1606f649dc883f---zaxobuxegimonisevilapa.pdf
    • http://hotechike.com/files/files/konavow.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/2kmr40btenkgi82b15ep0rnr92/35056443975.pdf
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160769178e0481---natefobosurenukemuvapaper.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b336b6216fb---godoled.pdf
    • http://bostonmentors.com/userfiles/file/xegelojolunevobezobik.pdf
    • http://taeguektour.com/FileData/ckfinder/files/20210604_7787C072FFFCCF41.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608745ef3507b---42885928656.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=ace+sexuality+flag
    • 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_off0000c7cb.bin
b1f8729020c3a70c728ac8591fd1167db7a9a335533f876bfb56807e7368c373
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7CB 10484 bytes
font_01_sfnt_off0000dfd3.bin
37048310c2957fa0a82a0796db98251aa4d2f4a9a4bd3329921380b9a561f0e2
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFD3 16580 bytes
font_02_sfnt_off00010ae3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE3 16792 bytes