Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a76f81b08614569…

MALICIOUS

PDF

109.5 KB Created: 2021-06-29 13:28:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: dee1d63ce0895e018c9905a3eaeed956 SHA-1: 7c5e24975fe6f5497a9b9c6e1a4b448ceb799b79 SHA-256: 3a76f81b08614569dbe18d8351f880e8823a8618adb153911fb3711cb2c539de
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 WordPress sites or disposable hosting. The ML classifier strongly indicates maliciousness, and the link farm behavior suggests an attempt to direct users to potentially harmful content or phishing sites. No scripts were extracted, limiting the analysis to the link structure and heuristics.

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://rainbowcaterers.in/userfiles/file/mixepe.pdf In PDF document text
    • http://lycee-elm.org/userfiles/file/wotodigi.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/03b8d512b6592957bed46ab967990592/45359552253.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/gotijovolagewa.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0212ca420c---fopokesux.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/8icj6fnh431526g7j7c8robt95/kazavadelaziguxe.pdfIn PDF document text
    • https://maisonforville.be/documents/file/weruvulod.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7c7d0c078---dejamodukolob.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/8281bcff57ef72fd66feac7e7c6ca91f/nokuvedalaledelojubu.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/31515615457.pdfIn PDF document text
    • https://oklogistic.lv/upload/file/63719891326.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/tetajikin.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/9b25fc881e48d5cc7558e881d387f6d2/30577592769.pdfIn PDF document text
    • http://munsusa.org/userfiles/file/20210628033137.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/724c11bf58908cf0ace61d6badeb3eaa/50760233452.pdfIn PDF document text
    • https://hotnews.md/upload/userfiles/files/nawixejepekusojunag.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c919beb028a---vaxon.pdfIn PDF document text
    • http://uhli-janmaria.cz/userfiles/file/bepewoxedaju.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3cd38b7713---nevidifisubuzufopodipe.pdfIn PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/053d4792f442fdb49ac845f947da50aa/84592485616.pdfIn PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/3b827541004f865906cfbe6a3445e315/xafuwa.pdfIn PDF document text
    • https://gloriouz.in/ckfinder/userfiles/files/ridukuzogofifabifawo.pdfIn PDF document text
    • http://nguoigiupviec99.com/webroot/img/files/1974931553.pdfIn PDF document text
    • http://penzionklara.cz/userfiles/file/14657925343.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=hugh+laurie+knightedPDF 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_off000149ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149AB 10420 bytes
SHA-256: 81d33815a1ec02fdf39803792a0f52ec4e960a7c7dc51ce3b1bf6b6b9d05e06c
font_01_sfnt_off000160e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x160E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000178fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x178FA 18276 bytes
SHA-256: 5f1e36d8c581e6b9546acbff1eb2df7297c5353460f19086dd57769595e452e4