Malicious PDF — malware analysis report

Static analysis result for SHA-256 c94c1c4c72855c32…

MALICIOUS

PDF

85.3 KB Created: 2021-08-08 00:36:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d42f5358694ac38c68d8dc6093c855f2 SHA-1: c3ae0d7268033b4cb2d5eac77eb1a6d0e409d9f6 SHA-256: c94c1c4c72855c3272c7f6c6b822dbff8d8abda79fde6f96746e6dafc03029a9
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and other disposable hosting, likely to redirect users to malicious content or phishing pages. The presence of multiple external URIs and link farm heuristics strongly suggests an attempt to manipulate search engine results or lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 http://noithatdangcap.vn/app/webroot/uploads/files/38713413028.pdf
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/695fe56e2051a8e6f02ed3cad513facd/42721434282.pdf
    • https://ebooksweb.net/files/file/53095430290.pdf
    • https://electroagro.es/pub/files/92700857578.pdf
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/cbe6847cf4591fa604a3afca6c0d2e89/28046806224.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/nhqvu8tpe5jcf3giis1t1mhl7u/wapapamodofepumisojig.pdf
    • http://chiangmai-clean.com/user_img/files/13778124598.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608679c38fb5d---tepeg.pdf
    • https://amursvoidom.ru/media/files/42622885820.pdf
    • https://chaletsuenodesol.de/files/69779312253.pdf
    • http://hasici-pristroje-eshop.cz/files/file/bodorevubefozebajiw.pdf
    • http://africa-emergence2019.com/userfiles/file/4561472020.pdf
    • http://gilendor.cz/userfiles/file/74799894063.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aabe635dd8---vawumeravekafetezuvonez.pdf
    • http://calhi1974.com/clients/46234/File/mivesipujoropedereje.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609b6a822fb41---25134017053.pdf
    • http://briarcliff68.com/clients/71184/File/36541361178.pdf
    • https://mobiligennari.com/userfiles/file/96637006757.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160f8e76411945---10950521971.pdf
    • http://sl-light.ru/design/img/upload/file/96549041512.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f42d7908d0---31725066005.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+do+i+write+an+acceptance+letter
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eab6.bin
bef3d16af2ba95f7d2cc0f1ad29037bec21c1cc23c28f1cd4d70f6615ca8a1ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAB6 10416 bytes
font_01_sfnt_off00010262.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10262 16792 bytes
font_02_sfnt_off00011a74.bin
870a763cfbc1c82243e04dcfb92ef949de781208444dea6d348b0e6a21b90427
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A74 16984 bytes