Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7661cb861d6f16c…

MALICIOUS

PDF

86.8 KB Created: 2021-06-29 14:42:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c0cf2a478bebbefd5fe95ef7539fb268 SHA-1: 876f99ff4845a3308645ddc199166b3f0c388d65 SHA-256: c7661cb861d6f16cf91e64c214dca3dd352b5053646a5dc38ebeefbfd45c5736
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b436bee43---75698482400.pdf In PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef828eac78---39249044034.pdfIn PDF document text
    • http://elitvorota.ru/f/file/14478758458.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/bfc5d6cd5abe955b0d5bf8caec8c7cef/kafaxaminiselomu.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/lidvn8tc36mo6091rifva016k4/pevofarotubiditazopos.pdfIn PDF document text
    • http://digemnd.com/UserFiles/file/xonak.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a68d5b13eb6---wasesonemozufelexerako.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b329b487560---gomalebubufosekebu.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609eb8fa8e653---bifusomijadikadasur.pdfIn PDF document text
    • http://coiffurenais.com/userfiles/file/bopimavasezupasumazafo.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/160ac15e1e964c---81795418234.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/37c221c1f3d47bfe673f3c12989b9292/93456061490.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/724vli98tv906rd9sdrq1ij7b6/2663251862.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/3783216348.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af7e13a4ad5---77087586832.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/dtqvatg0pjqhg5t0rprh74sucp/vojexanozereregejipotu.pdfIn PDF document text
    • http://fipjp.com/userfiles/file/47351822441.pdfIn PDF document text
    • https://hssipm.com/wp-content/plugins/super-forms/uploads/php/files/28b55f3e97998c0be7ca528f1c00b759/dawulipal.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d472b312a8.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/3813e349c21895b1d44c03460e59d860/gimegububuk.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607781b584017---74263125318.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/d20188b3a58f636fe87f0b488c59522a/sutubujupafenomonuv.pdfIn PDF document text
    • http://hasyo.net/files/file/37374899400.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/ae22135f2a7913a67ecccd67de664f4f/68852679720.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608138be98a33---2144420012.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/3qnd1jg58g2covn5pnjpdtls61/luraxeli.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/5m2g27r2obk655ltk1vemnqnuv/senisogapufel.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/47412674853.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=mathworksheets4kids+exponent+rules+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_off0000ec50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC50 10940 bytes
SHA-256: 5c506b044996bf9eee8199afd029cce8c4a041b9787738714e2e3d7e0cd9d99a
font_01_sfnt_off000105bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BB 17932 bytes
SHA-256: e8dcc755b2447ddd008e672f08bde91c7607ca81873b06868aee3af14aa3142a
font_02_sfnt_off00013560.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13560 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1