Malicious PDF — malware analysis report

Static analysis result for SHA-256 50dd993162697baa…

MALICIOUS

PDF

69.6 KB Created: 2021-10-01 02:11:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 500e0c31d1b4d722dd45d3a4f5ef1fc7 SHA-1: c034985126d6457deb8624d23d7b4e51e87152fb SHA-256: 50dd993162697baa7c80c5ef3d97bb66e5fe19fcdee23ca65a631947853aa896
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic confirm the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://crysiq.ru/uplcv?utm_term=how+to+bypass+a+lock+screen+on+an+iphone PDF link annotation
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/5a0f22ffb4d7d565332805a3550dcb45/15760948371.pdfIn PDF document text
    • http://darec.sk/files/files/nekedijaxatonulixudelikib.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144e04443087---85736820183.pdfIn PDF document text
    • https://mygoaltv.com/ipp/images/uploads/files/wapususugavapevezopuroken.pdfIn PDF document text
    • http://sportingfoundation.com/uploads/file/27668771543.pdfIn PDF document text
    • http://bburago.info/admin/fckeditor/userfiles/file/20623686265.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/74900061317.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/kulofifusibovikivosama.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/23704533452.pdfIn PDF document text
    • http://fabriziocar.it/userfiles/files/varogugutumakusaga.pdfIn PDF document text
    • https://szallas-karpatalja.hu/upload/78371956148.pdfIn PDF document text
    • https://aczv.fr/userfiles/file/konejofitaseromob.pdfIn PDF document text
    • https://chennothinterios.com/uploads/file/901931562.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/66575789101.pdfIn PDF document text
    • https://lrsinc.co/userfiles/file/51430838664.pdfIn PDF document text
    • http://wernersuarez.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zorumopusubemikekak.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/15830911630.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613abf62c2a78---lenotanamesinijot.pdfIn PDF document text
    • http://vandientuchinhhang.com/upload/files/ludijozuduvamapazu.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148885b4c710---39376551813.pdfIn PDF document text
    • http://improntediteatro.it/userfiles/files/gitojonusugevaw.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/13012953641.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_off0000adfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xADFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c60f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC60F 16664 bytes
SHA-256: d4239350f345a0036b4669c33eaf91740ef0c558fea3c546446097598e7506dd
font_02_sfnt_off0000f001.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF001 10892 bytes
SHA-256: 988a0a7968bd1ce9a73ee9db53ea9f97c6ced7ab1e2b1db88e6d0d37b2eb6750