Malicious PDF — malware analysis report

Static analysis result for SHA-256 f52d03892aa5e9e4…

MALICIOUS

PDF

81.2 KB Created: 2021-09-02 05:15:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: fee90e2c6d75763979b0139b983bd56e SHA-1: f9d2ef4770ba53e782cce19545d53f17ff7e6542 SHA-256: f52d03892aa5e9e410d1d5b814228b17a91a159707849ff2203acf4cc1a65d34
96 Risk Score

Malware Insights

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

This PDF file was flagged by an ML classifier as malicious. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting. The primary purpose appears to be SEO manipulation or redirecting users to potentially malicious content hosted on these compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/f69d384d87b5674967cb3907be5366a1/77770795534.pdf In PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/9f584a0ded760fa264600acbe980c5fb/92584580405.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/fomoxusokima.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084530c1b54d---fobezolifuxavosamu.pdfIn PDF document text
    • http://ncdesign.it/userfiles/files/12495736284.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608a4136cc15b---46772054293.pdfIn PDF document text
    • http://hocikto.info/userfiles/file/84613495618.pdfIn PDF document text
    • https://cochleartudaskozpont.hu/files/36017871425.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/t050pkh4fslfe2ahua0e335h06/2374670075.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/junijilikatej.pdfIn PDF document text
    • http://jrmhandling.nl/upload/file/53099808044.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609466d09834a---gowosejel.pdfIn PDF document text
    • https://topplene.com/upload/ckfinder_temp/files/20210621171003.pdfIn PDF document text
    • https://digireg.it/upload/wetajog.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/beab4074e5e2ca8ff18fd3414152bed0/25290367249.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/66530042795.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081b3625db53---4666454552.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a4d1475b84---balutolosowexu.pdfIn PDF document text
    • http://vvk-wiedermann.at/userfiles/file/15407069023.pdfIn PDF document text
    • http://burmeseburmilla-allevamento.com/userfiles/files/4849474623.pdfIn PDF document text
    • http://innotack.com/userfiles/file/basibemiwitefofomid.pdfIn PDF document text
    • https://khonggiansangtao.com/platformecom/img/upload/file/bazoladisiw.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/vomizidito.pdfIn PDF document text
    • https://ocw.tw/uploads/files/11333428625.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=zack+and+cody+odd+couplesPDF 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_off0000d724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD724 10484 bytes
SHA-256: 2219e77575094e52e887713ee4c2654930b2db4e1e7ac2f6cd0e31d56f8be2eb
font_01_sfnt_off0000ef2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2E 18844 bytes
SHA-256: a418887599007159a4726f46de9484df86043839f5b011d688fa7faae905725a
font_02_sfnt_off00011fbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FBE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1