Malicious PDF — malware analysis report

Static analysis result for SHA-256 50ec7203c6d38124…

MALICIOUS

PDF

102.0 KB Created: 2021-07-21 05:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ebc37cc4d050b4b2a53e84145a49b20d SHA-1: 7881a3748dd18ca741a22aa7c205e09b0c17cb1e SHA-256: 50ec7203c6d38124752e24f719798fc7b824e094a67e0a60da8f5ce0fbebccf9
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised CMS upload storage or disposable hosting, indicative of a link farm. ClamAV and ML classifiers flagged the PDF as malicious, specifically as a phishing trojan. The presence of multiple PDF links and the overall structure suggest an attempt to manipulate search engine rankings or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9931

Heuristics 6

  • 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.
  • 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://phucatgarment.com.vn/ckfinder/userfiles/files/wowekuwujudaxililorupej.pdf In PDF document text
    • http://sklepjola.pl/userfiles/file/78801952359.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/mlqs0o99l5shlrkhqr3g5fgafl/17009037117.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/f912bf18c912ebe9bba74ef455e44e3f/97799104616.pdfIn PDF document text
    • https://kermanrooz.com/img/files/67456268204.pdfIn PDF document text
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/6ptafabsko626srdrtibefjckr/bujoziwofeba.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/u87s8bq7isqktkl42oe724bm5o/56808524308.pdfIn PDF document text
    • http://tevukasveza.lt/ckfinder/userfiles/files/87339596527.pdfIn PDF document text
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/3ce8d6adf7186faee43f0f2b0e00dfd2/gurujekixakawuxabufutob.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16094aaa6cd82e---telujiluxew.pdfIn PDF document text
    • http://mlsconsulting.net/cms/files/File/89921859056.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/c9182387322033971830de717307c33d/71020556893.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/kokikabaj.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/57504315193.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/fefaderinuvi.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/1b6e1f67821e6ed93f6ac000d5dea7f0/ranozujofofixito.pdfIn PDF document text
    • http://dzbnf.com/upload/file///mujelerutorogivub.pdfIn PDF document text
    • http://gmei.lt/ckfinder/userfiles/files/zofikesepadefotizobi.pdfIn PDF document text
    • http://herningbadintra.dk/app/webroot/upload/files/dadazepidog.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/muvav.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/90aa7bb4be6bed46b3e0decd892bcbdb/89088922873.pdfIn PDF document text
    • http://spalovnachemolak.sk/userfiles/file/50463634604.pdfIn PDF document text
    • https://egokituz.eus/files/galeria/files/kimet.pdfIn PDF document text
    • http://pm-property.pl/userfiles/file/39326945341.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=minecraft+floating+island+seed+bedrock+editionPDF 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_off0001282c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1282C 17932 bytes
SHA-256: 306a08ead039a7e3469f77311aab2aaf2d11a811beda679ceea8c11f7c66e5ae
font_01_sfnt_off0001575e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1575E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016f75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16F75 10876 bytes
SHA-256: 253660b3049372df8841fe8415184211935758714a703f24ff3ea31f356a59d7