Malicious PDF — malware analysis report

Static analysis result for SHA-256 b691068867a66c9e…

MALICIOUS

PDF

82.6 KB Created: 2021-07-14 04:29:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 297f35f49c65fa3e1e7b3bb7140e5e3d SHA-1: 31db624bba38da713cb7225a63f454ee9b844c26 SHA-256: b691068867a66c9e3c2b16773655ea84a98ebbebefa94c66916030be90af95eb
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm pointing to compromised WordPress sites, which in turn host other PDF files. This suggests a multi-stage redirection or phishing campaign designed to obscure the ultimate malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/bkj14onv4csld3i7rcv7nspcd0/tajuguguxewi.pdf In PDF document text
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/xevagaroxota.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a681d3af1f5---99180664371.pdfIn PDF document text
    • http://haumeaonline.com/userfiles/file/841599605.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/5ad2ba2c3eb333f0f3933bd3c4b4d28d/jujoxefisofodiroxo.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/57377517426.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160913b167cf49---87961958435.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/butavopasefija.pdfIn PDF document text
    • http://congtrinhnhaviet.vn/upload/files/leniwikina.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16080ab02af709---pupetobuguwewexenobedir.pdfIn PDF document text
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/17a86e59810c4076c04f5676968b2e8b/78477440557.pdfIn PDF document text
    • http://yule-sign.com/upload/editor/file/20210620121738.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ba9f66ac9d2---nefukizidene.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/2b7962vq8fegqh9a8rf95nkjb3/45810737289.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/sp67gth7v2tprl74dvfj9d35d5/258663014.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/rovowekedowem.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-25/20210525131210312419.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/57052880424.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/nofefikixetazepuwuru.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c350d28e0c2---xiponugewejemo.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc8271038e---16070201830.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/61894085182.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/damedup.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/acbd73d524d0f9f6c7e00fcf28987477/wulejunik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=right+side+hitter+volleyballPDF 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_off0000e354.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE354 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB6B 10788 bytes
SHA-256: bd9011594528d9d1270858c84b986db1c07bca8cb094dedeaad177f52ce9eaab
font_02_sfnt_off00011434.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11434 15940 bytes
SHA-256: 82be072d5b6fd4616330329ff255b2c9e8c4d37339fdca2c04849ff24227a1ab