Malicious PDF — malware analysis report

Static analysis result for SHA-256 e51afbd3e92c5eec…

MALICIOUS

PDF

71.0 KB Created: 2021-09-30 12:24:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fcffdc66e71463ef5f6973ca71810178 SHA-1: c1a40ebd18f787eace45dbca6da16b8777904c93 SHA-256: e51afbd3e92c5eec98b8219b5821125196a3c2f3758f70e7c4e9cfa49f392835
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it likely contains malicious content. The heuristics reveal it functions as a link farm, directing users to various websites, some of which are hosted on compromised CMS upload directories. The presence of multiple external URIs and link farms suggests an attempt to lure users to potentially malicious sites, possibly for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://elektromig.pl/userfiles/file/xetelawuma.pdf In PDF document text
    • http://sriraghavendratemple.com/ckfinder/userfiles/files/bowijubekizuxetol.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c01d7313f---xisumafa.pdfIn PDF document text
    • http://gdlianyu.com/uploadfiles/file/zepapumatofokudulofu.pdfIn PDF document text
    • http://acupunctuuryao.nl/ckfinder/userfiles/files/87090651670.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/a1dca88457b8fd6542855bf756db691d/18914288216.pdfIn PDF document text
    • http://kbidc.kr/upload/editor/file/1630852579.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/3f4qna8g5epae566hgb43bglmu/18181877187.pdfIn PDF document text
    • https://activsport.ro/userfiles/file/titajaregovajovuve.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613099b965fc2---lavewabixagekapewuvuwomi.pdfIn PDF document text
    • https://wemservice.com/ckfinder/userfiles/files/sagepubajebisotivapujefa.pdfIn PDF document text
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/rodurir.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/17776240735.pdfIn PDF document text
    • http://szpitalstrzelin.pl/userfiles/files/63207780430.pdfIn PDF document text
    • http://ckud.handysociality.com/upload/files/9456435386.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161444056c07f6---20782493170.pdfIn PDF document text
    • https://24emk.ru/ckfinder/userfiles/files/nuxekebibudegoganoja.pdfIn PDF document text
    • http://pfollowers.com/ci/userfiles/files/wigewowidezogojinutupu.pdfIn PDF document text
    • http://mc-opony.pl/files/file/7320886965.pdfIn PDF document text
    • https://ww150005.linebot.net/upfile/files/20210929101336.pdfIn PDF document text
    • http://hdurmuslar.com/images_upload/files/61109023391.pdfIn PDF document text
    • http://cocoon-source-harmonie.fr/public/file/budiribo.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613889b9ab220---talewarusomub.pdfIn PDF document text
    • https://kolegium.inaheart.org/upload/files/mepuruxoxemikipusu.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/ep6ohleuvabrlrqt6iuha7lc04/55657345368.pdfIn PDF document text
    • http://zaiger.ru/img/file/rodajapu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=making+thinking+visible+routines+pdfPDF 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_off0000b574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB574 15444 bytes
SHA-256: af4b933b5272f2cd2e1013721e8a49c1521d5718ba36ed999afe25da06176057
font_01_sfnt_off0000dc63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC63 11168 bytes
SHA-256: 6ae70bc3c1f5e69ccc596338cfde0aa6130c3eff5c205e4113d9a2e741593938
font_02_sfnt_off0000f60a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF60A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1