Malicious PDF — malware analysis report

Static analysis result for SHA-256 8862610158dbec5e…

MALICIOUS

PDF

82.0 KB Created: 2021-09-17 04:57:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 154842a7c5f7b922075bb7a524e74fe4 SHA-1: ee942d7dad3d6814760c4a2f5ae6cd29b363a123 SHA-256: 8862610158dbec5e72c263ca5aee86de293230c694eb7ddd3123a926953bfe2c
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier strongly indicated maliciousness, supported by heuristics identifying the PDF as a link farm pointing to compromised WordPress uploads and disposable hosting. The embedded URLs, such as https://inwebjor.ru/uplcv?utm_term=genshin+impact+gs6acj775knv, are likely used to redirect users to malicious sites. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 https://inwebjor.ru/uplcv?utm_term=genshin+impact+gs6acj775knv PDF link annotation
    • http://crocepadrekolbe.it/userfiles/files/saxuxafadijoga.pdfIn PDF document text
    • https://ctsgroups.asia/images/file/siwadojolejeronidep.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139caac93a55---muwoliniguxi.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/16139053caee7f---14174825541.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/kanopul.pdfIn PDF document text
    • http://netmode.net/app/webroot/uploads/files/83190880486.pdfIn PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/53376654598.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202109031621271822.pdfIn PDF document text
    • http://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bupuvazasad.pdfIn PDF document text
    • http://ser-buk.com/userfiles/file/35997828657.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/78136254843.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/33982216055.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613019bbb8eff---vusesopogamevexupeni.pdfIn PDF document text
    • https://mashura.co/userfiles/files/40572097934.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613051bedff60---xulufeve.pdfIn PDF document text
    • http://logicparcel.net/uploadsEditorfile/sijetowof.pdfIn PDF document text
    • https://ozanetiket.com/TasarimAcarnet/serhali/upload/files/dadogilame.pdfIn PDF document text
    • https://27061010.com/uploads/files/202109151631412704.pdfIn PDF document text
    • http://cluboutletmoto.net/campannas/file/61472166531.pdfIn PDF document text
    • http://notar-frings.de/userfiles/file/94480201311.pdfIn PDF document text
    • http://dejede.com/userfiles/file/80699330393.pdfIn PDF document text
    • https://grandiosieventinuziali.it/filesUploads/file/48793470614.pdfIn PDF document text
    • http://centralgiving.com/media/userfiles/file/rawigiredaloziseli.pdfIn PDF document text
    • http://conditum.nl/userfiles/file/7812451648.pdfIn PDF document text
    • http://hwayoung.kr/upfile/files/37348650512.pdfIn PDF document text
    • http://xz-brand.com/ckfinder/userfiles/files/zisotobexuma.pdfIn PDF document text
    • 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_off0000d975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD975 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f18c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF18C 11236 bytes
SHA-256: 2911bee5e1f5116df2828653128d98d725754575dc2e8ab42c235166a9db9242
font_02_sfnt_off00010bd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD2 17908 bytes
SHA-256: aa74a9666b1201248fb41cbafee3f4b98a34c65a6d448add6801790194d131b9