Malicious PDF — malware analysis report

Static analysis result for SHA-256 7725df8d7b4111b2…

MALICIOUS

PDF

73.2 KB Created: 2021-07-03 17:51:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 450fc60e48b5599591eae88c29d93da2 SHA-1: 1345c042a767b205160b6ac58900af8a97682a80 SHA-256: 7725df8d7b4111b2b1411c3f77cd912fe5412689ba6a0eed9eb4df120832f778
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, suggesting the document is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://lmyc.net/clients/875386/File/tuvivuz.pdf
    • http://dobrasekacka.cz/userfiles/file/35932456117.pdf
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/d4h33e0npev36m16slqf256v01/98524914212.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/87tis9p182v4j00ounaid2lbh0/silezuxisifa.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d9e7a1b2e---31104045888.pdf
    • https://noventa.cz/media/files/file/51457013361.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160901ec2b9280---domadezewavoju.pdf
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160906075a25d1---62523608194.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609185aeb5b53---300919144.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/2d1c093822c45652eb3fb5424d97bb9d/32142007310.pdf
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/61848490786.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c52772befe1---9587959792.pdf
    • http://www.dereformasenalicante.com/archivos/files/73463999816.pdf
    • https://medicentrumnz.eu/medicentrum/files/file/90136149295.pdf
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/677b06104272c6797b505b25707c0baa/91447732796.pdf
    • https://muratay.nl/userfiles/file/nuxuratewudovetekamijado.pdf
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/c485ede615227fc951b81721abe93196/letarozutirazixut.pdf
    • https://qqhanoman.com/contents//files/20100551983.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/n6b8vdle66gqu9uobv2df4kco4/79835094795.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c141be48ccb---8661312533.pdf
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/8da9317ae990641f0f10efa50975989b/pazowalivaniwiwi.pdf
    • https://thietbivesinhanhhuy.com/asset/files/8696956383.pdf
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/a5f8c93d368fe16cefd44e938c7e8112/mibojebovefop.pdf
    • http://lsbwg.com/ckfinder/userfiles/files/20210619/2121379971.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=top+tronic+timer+manual
    • 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_off0000bfd2.bin
ef535c6065573643470432540375a23197ac2f5f1e8de2e71768576837742a2d
pdf-font-stream PDF embedded font (sfnt) at offset 0xBFD2 10428 bytes
font_01_sfnt_off0000d769.bin
323de32eb32a9d88c8eaaf32a966bdeef6592cbe51e604c77a995b8a0b49329d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD769 15632 bytes
font_02_sfnt_off0000ff84.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF84 16792 bytes