Malicious PDF — malware analysis report

Static analysis result for SHA-256 983df0802c306dde…

MALICIOUS

PDF

74.8 KB Created: 2021-07-03 18:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 51c73e727097267c975ff65a1facda47 SHA-1: 23752ef20d403b143f11a5b62d9b9e6a8dd041ce SHA-256: 983df0802c306dde5688570a67912d7a750378729470aff12f6345ea0875804e
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external resources, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to download further malware or engage in phishing. The file's structure and link farm nature suggest it's part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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 http://khiconghoixuancong.com/Khicong/admin/userfiles/file/nakokonikiwokamukarapef.pdf In PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160aa8d153fe6a---ruzulidowaxas.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4b9fe9a8c---10062110974.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/64621664299.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093e1a0ec2c6---xovimif.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/d49bb73e4d1a66ae3d4a2e84bf9a1e60/78422033444.pdfIn PDF document text
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608848226b1db---23512338953.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086f213348dd---32529909551.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/4chvd87o1ghjc9hu5j33glnh80/8546037293.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/jbti1gk6d9eu7t5c8q2vi6vql0/turawalonupub.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b874aa8ecc---28310451519.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/48147b0da3e2a1607af18bbbce71bf50/25633396505.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/fe7dfea56284b93eed872e68a40d8442/61485838011.pdfIn PDF document text
    • https://slaterlighting.com/wp-content/plugins/super-forms/uploads/php/files/dcd80b8d843f6ca08a3f0c3775334344/69150590538.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/160caaaeea4dd2---50876520862.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ad6fcbb9b2e---nemoxuniwususotupedaxilug.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/nsgao645mecnn8jujclmgbsfhl/bubuwo.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8f9e2c301---jugazer.pdfIn PDF document text
    • http://carszana.com/image/upload/File/78125661707.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160933d9073d0e---gewabilabuk.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/a1a332b77715ea4bb2893cfad690137a/siwugulizozukuteweji.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/n88d1vjg4sn6duk9k07eac1b50/32246310686.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/9f59533beed10127eab3fd1111adcd8e/42930652974.pdfIn PDF document text
    • http://munsusa.org/userfiles/file/20210621110619.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/a81d433223b71b63b40107caf8e45d7e/19353200910.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bf95dbbb34c---rutamerabejoxudoxogored.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16080f7e0b699d---48529567187.pdfIn PDF document text
    • http://lhsclassof68.com/clients/73441/File/tuzelud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=24+game+answersPDF 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_off0000c383.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC383 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB9A 10284 bytes
SHA-256: 4903f5c22e78a51da3f6903601e0ede1ee2c748288bb0a0cd3fe653e5512d825
font_02_sfnt_off0000f2d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D5 16720 bytes
SHA-256: 93856732284285d18e71c87bf5c543206531d1774ab19becfedb965653f2d755