Malicious PDF — malware analysis report

Static analysis result for SHA-256 e246a4beed82c26a…

MALICIOUS

PDF

79.3 KB Created: 2021-09-11 02:37:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 16dd485215e938f2dfa4a67d39c21add SHA-1: 29162aea000cee0b0b67ba104318af974c1cb801 SHA-256: e246a4beed82c26a6876e0cecdb00c5ef2a57600b6e3fa904837b226cbeb96ac
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm. The ML classifier strongly suggests malicious intent, likely for SEO manipulation or to host malicious content. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • 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://rkenterprisesonline.com/FCKeditor/file/wujetupafawex.pdf In PDF document text
    • https://seikai.jp/free_images/files/26085254068.pdfIn PDF document text
    • https://butzbacher.turnpoint.jo/app/webroot/upload/files/fepofa.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/wuritulediwut.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16134ddc3bf083---45023479969.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16132362b4cfe9---62004813092.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/16142619140.pdfIn PDF document text
    • http://vp-dmsh.ru/admin/ckfinder/userfiles/files/nowevemu.pdfIn PDF document text
    • https://titishop.co/upload/files/43069784420.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///romabavawijubejesawa.pdfIn PDF document text
    • http://tainanrup.longi.tw/uploadfiles/files/20210905_100118_4500.pdfIn PDF document text
    • https://www.pension-chevaux-haras-gabereau.fr/ckfinder/userfiles/files/76555984554.pdfIn PDF document text
    • http://kodemari.info/data/files/judufunikokexokefuvu.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/83314137282.pdfIn PDF document text
    • http://gespk.com/userfiles/file/50976678522.pdfIn PDF document text
    • http://fibertechnique.com/tmp/file/wutetoboxapinipiwunuja.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/bewop.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/59179629667.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/napazek.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/suxatapidavoxaguvipilod.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130cb32b6b23---sebugoguvejorixuzizi.pdfIn PDF document text
    • http://slbreakingnews.com/ckfinder/userfiles/files/sekep.pdfIn PDF document text
    • http://elandtour.com/FileData/ckfinder/files/20210911_86370971F6281795.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/44787106186.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=redmi+7+unlock+codePDF 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_off0000d29d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD29D 17836 bytes
SHA-256: a3a1e7c63441a93f5d9ecac9f4583900d483d2232ea7faf453a28b4f23f77edc
font_01_sfnt_off000100b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118CD 10292 bytes
SHA-256: 0eabe40896faa2e77ff201383782df3fa890fdedf7f73331bf329a033802e4e2