Malicious PDF — malware analysis report

Static analysis result for SHA-256 a23e3ca710c1845f…

MALICIOUS

PDF

82.8 KB Created: 2021-06-26 07:46:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 08a89e5f8aca2667c5f355c388b75d58 SHA-1: 6e6f182e44013ccaaa67396dd9e0ee1dcd78d538 SHA-256: a23e3ca710c1845f778cd0344d1cc74d9c596adeeeada8eabd4854afb721fbec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm for phishing or malware distribution. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The presence of external URIs and the overall structure strongly suggest a malicious intent to redirect users to potentially harmful content.

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 http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b6571b990bf---2068010533.pdf
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/uefqoka1ir5qmskl222ah7euv6/mafonusajog.pdf
    • http://alibabashipping.com/userfiles/file/tadoxirusesu.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088bb1642e41---47889953882.pdf
    • http://modnyi-buket.ru/uploads/files/vatutimopigufiturexafiba.pdf
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078cfa31aa32---17130595219.pdf
    • http://tofuyatogo.com/uploads/files/sozigijipud.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16071f69b703e5---36308339948.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607925130f626---rakipoviraxakenemamitonor.pdf
    • https://actorconseil.com/files/file/27768260782.pdf
    • http://anhuifan.com/upload_fck/file/2021-6-15/20210615215957703253.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad8cf729757---mugawexedowadurof.pdf
    • https://baxsporthorses.com/userfiles/file/kenitepazifumeniz.pdf
    • http://best-infosystems.com/userfiles/file/53201989800.pdf
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/dddfedefb5690bc46f0f3f84b4802001/tarirukemiko.pdf
    • http://murphysbeads.com/clients/54316/File/59065925588.pdf
    • http://forter.vn/hinhanh/file/31697310898.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/6c8f34b183210f9c21a05ec31f436054/sowiromarunititidepebep.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160868c8b9bdb3---kazuvikugu.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/o40mfrkp46k4qi82o9tkh52930/17532881201.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c6aab78398d---xoxala.pdf
    • https://asset-books.com/userfiles/file/5328877675.pdf
    • http://andrenickels.de/ckfinder/userfiles/files/58339605105.pdf
    • http://peaceinsrilanka.lk/userfiles/file/demadatudamuvumopel.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=game+tic+tac+toy
    • 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_off0000e0fe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0FE 16792 bytes
font_01_sfnt_off0000f915.bin
6cd1b56e899f279aa60a065d65394cdc99f833b3ada8a9709528f7f956ddf682
pdf-font-stream PDF embedded font (sfnt) at offset 0xF915 10124 bytes
font_02_sfnt_off00010fc9.bin
25752793dc32710c5b228b06c1a2cbc7bade867e5c2ca37da03c28af6c89167b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC9 18056 bytes