Malicious PDF — malware analysis report

Static analysis result for SHA-256 53a3834c090d12f2…

MALICIOUS

PDF

80.1 KB Created: 2021-07-03 02:37:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4fcc0b7dd9291d9a6b7ee43ca26be156 SHA-1: 2c81a2ff759ee820b74b0e76060492279d54f4d1 SHA-256: 53a3834c090d12f2ded5533cc59187ddbead5e10f7e5d0208ad30b913a7cf76d
164 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous external URLs that point to various websites, including those hosted on compromised WordPress installations. The presence of 'utm_term' parameters in some URLs suggests an attempt at SEO manipulation or tracking. No scripts were extracted, but the document's structure and URL distribution indicate a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://philabc.ru/uplcv?utm_term=ben+10+alien+force+vilgax+attacks+game+for+pc+free+download
    • http://www.alex-vasilkov.ru/images/wisdom/file/65121133672.pdf
    • https://alianzatours.com/imagenes/file/94036643067.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d51e4d92d8e---jirifazirekoreg.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a0b364cc2a---xetoluregovi.pdf
    • http://hobbstownis100.com/clients/6/66/66141d04a4341350d76ae3a38785cb5a/File/mufufuguvifevokekekoluzu.pdf
    • http://classicalgardenstatues.com/uplds/file/77769655481.pdf
    • http://archi1919.com/smlclub-files/file/42694492813.pdf
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/tomilatamakoj.pdf
    • http://hopkinshigh1966.com/clients/1/10/1054c114374c88b4a165e91103565d41/File/62099581607.pdf
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d0afe54242---fapujumirevedebani.pdf
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/028ro37s51rqajrt5fifjoiej3/rusobokoxiz.pdf
    • https://www.ppmcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/4sbr05ofunhvr0cvadmhfh4dq4/42303104573.pdf
    • http://www.grifin.sk/files/vuxojisibuneremonalegunu.pdf
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/10ed648e087dbfe1a2db19d6b4795525/jaretomagupusigefifiwaba.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b85db9ede33---15132492987.pdf
    • https://e-fasteners.eu/media/file/99051063869.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/213nb2f5b18tukc1sh70cp3r2c/81241866793.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c04a1d931a0---tukunap.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607176d864079---25290907397.pdf
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/f8ae662593b12bdf531bcb512f540146/66480424979.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/sd2jsarkvlvgat2374ap2ud9l2/62503920354.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/b283a0eec9a7f6b763350aef053a5d68/vumimigejijene.pdf
    • http://clinicaveterinariailmarzocco.it/userfiles/files/buwigikixome.pdf
    • http://piotrkowska77.pl/zdjeciafile/26734835576.pdf
    • 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_off0000d1d1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D1 16792 bytes
font_01_sfnt_off0000e9e3.bin
ba110278c51c0208a9903a14fcae59c9de1b904853f705ea2e9014f674ea0448
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E3 17252 bytes
font_02_sfnt_off00011733.bin
faceb02a20a1d59f3ded89661f8d34d04187cc01568e7722013b5d3be58d6ffd
pdf-font-stream PDF embedded font (sfnt) at offset 0x11733 11536 bytes