Malicious PDF — malware analysis report

Static analysis result for SHA-256 b91b0f866c1966ca…

MALICIOUS

PDF

77.4 KB Created: 2021-08-28 19:21:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7e95ded37bec4afece4526159095d020 SHA-1: e3725922d31e86c8a35984496d567b8f2e03f85d SHA-256: b91b0f866c1966cacd72fbecdcc0c9cffbb486b9ee813471323f30b5aa08c339
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various websites, many of which are hosted on compromised WordPress installations or disposable domains. This structure is characteristic of a link farm designed to distribute phishing lures or malware. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

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://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160926c9e8d9e4---24198784497.pdf In PDF document text
    • https://ksmt.edu.np/assets/ckfinder/userfiles/files/xagix.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/160832378cb781---99060546249.pdfIn PDF document text
    • http://80tner.friend-match.com/upload/files/pirakamajopabuzamezona.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160991d5969db7---46227222869.pdfIn PDF document text
    • https://ranagro.com/files/19023636381.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/d2bcdacf10f34cfbff8fe80d7986497e/9622591524.pdfIn PDF document text
    • http://doubler-son-capital.com/photos/files/naxuwoxunaxesunigupan.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1b55236f82---lozolidoputu.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f4793d1ee08---9948072851.pdfIn PDF document text
    • http://goldmustang.ru/files/files/fexuxofutifadapapuzavobu.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6acdbded7---monedirexijeka.pdfIn PDF document text
    • http://www.chiringuitomediterraneo.com/ckfinder/userfiles/files/81801466353.pdfIn PDF document text
    • http://world-green-hope.com/uploads/files/33172513192.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/96333151678.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/44a529eb78901e9500620ba51047942d/mejesap.pdfIn PDF document text
    • https://balaji-technology.com/userfiles/file/53752611938.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/zufofigidagodexux.pdfIn PDF document text
    • http://msdoubrava.cz/foto/images/file/46353602765.pdfIn PDF document text
    • http://khmer24biz.com/public_image/alluserimages/files/14836931600.pdfIn PDF document text
    • http://qca.ch/userfiles/file/fejexoniwelo.pdfIn PDF document text
    • http://csc-0898.com/userfiles/file/20210802073838_yonmlt.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16121ba869ad60---73647121104.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/79276365008.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/160992ceb768f7---28791359492.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/miwulogilevuziregavawojef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=anemia+and+hyperglycemiaPDF 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_off0000ce47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE47 15768 bytes
SHA-256: 32c78042d801bcfc0b7cda94700e9123991eb50fbbe098398369b1663dcdc5f7
font_01_sfnt_off0000f708.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF708 10672 bytes
SHA-256: 1ddefa2fff4c2bb0d24a382b11237ac5af36e9c0fc6c99d2e2a87292c9b9b633
font_02_sfnt_off00010efd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1