Malicious PDF — malware analysis report

Static analysis result for SHA-256 173bd6582db4795a…

MALICIOUS

PDF

81.0 KB Created: 2021-07-22 22:59:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3b98ccd3ff835b233d99afd428ea705a SHA-1: 4960a3c681de7d7fed59e0f9295a701f6ffec9c0 SHA-256: 173bd6582db4795ad67a2bf500097866a2d2e369ee0c9a5506c23a72049cae16
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://lapenya.cat/imgjovesnaves/file/xenavow.pdf In PDF document text
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/27902302935.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/begapapunarigu.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160d75801ace37---19993761256.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/eapic2pif07e5n6rk9f8lv51fs/4100412856.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f27948066f---resaturemomeje.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bc264056c98---56789439365.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dbbbe5099e---wofifopajunego.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/40501281380.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/labonalirobaxelesisejo.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608593faad8dd---rulukel.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091a1136041f---zezifizedanupisi.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160d1de8e29f49---bukivemoxobozuwogexevi.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad1f54e97e8---2942871251.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/c8f866c8d3dd88754b69716d13764f1c/23003380284.pdfIn PDF document text
    • https://dagvandearchitectuur.be/_files/file/45361626671.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16075acfee45d3---lofivopifopudofitirexu.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210706_023BFEFD56541361.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/51095934374.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/4b8fc2490706303b2f99ca91e2a216e6/39405868113.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088457f6d72a---xufuw.pdfIn PDF document text
    • https://turdv.ru/SITE/files/editor/file/13406753046.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/pmtv8i7abjpscsja0ip1d65vuk/44118286441.pdfIn PDF document text
    • https://vili-al.com/uploads/wysiwyg/files/puxafi.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16085838e5bbf1---nopapivelusosuxasudakaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=worksheet+of+direct+and+indirect+speech+with+answersPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a915b8d0f39---36582030753.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_off0000d793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD793 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA5 16888 bytes
SHA-256: 3c3758e208874871f9808e2ed80033dac8723281266de16e5308d358a26b372f
font_02_sfnt_off00011b87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B87 10844 bytes
SHA-256: 2dd9f86d89c0d495d89b402d344fd4601a2f342cfdc32fdd058476a8a056ba5a