Malicious PDF — malware analysis report

Static analysis result for SHA-256 2535b3eb460c1643…

MALICIOUS

PDF

72.0 KB Created: 2021-09-02 23:55:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 822f188af4b18cd43da8c366514f404f SHA-1: 38ec179ffa2c2b2f4cf9e6b1329f6f24c32c3f71 SHA-256: 2535b3eb460c164332cf48b510e913407d833bccb9a1cfa01a0a42e37d538a7a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of these links and the overall structure indicate an attempt to deliver a secondary payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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 https://travelworld.ro/userfiles/file/93278977618.pdf In PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609118d1a5cad---jozunaduruzadafawokuwe.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/10265546035.pdfIn PDF document text
    • https://kaplaitalia.it/userfiles/files/redukegiwigufasexak.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160862ab22a3f3---40857768336.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/46096479619.pdfIn PDF document text
    • http://scarpatti.com/files/fojobapanaduramufode.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6907cbe65c---57460277629.pdfIn PDF document text
    • http://berallebags.com/UploadFiles/FCKeditor/20210807053538.pdfIn PDF document text
    • http://iehyun.com/editorupload/file/xefotuledimugileveji.pdfIn PDF document text
    • http://whsclass1968.com/clients/f/f8/f849445bb2fb8f42e7c863050dc1ba38/File/nixewusiwoduresasegop.pdfIn PDF document text
    • http://tischlerei-schlusche.de/sites/default/files/file/53818874538.pdfIn PDF document text
    • https://tekartltd.com/upload/files/82653870958.pdfIn PDF document text
    • http://envigest.cz/upload/file/39137871728.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/cf3335a2af8c6fe1639d599d95d391d8/55374761922.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/70311638126.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/79s22udr0hj938btm2ahkrggq3/kodowabegajakegekukokip.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/qo1qkjaaql7u6a1ca71bgjrtb1/warefumunor.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/duzisolemipulixodewatax.pdfIn PDF document text
    • http://theettiares.com/clients/f/f0/f03dfc1790708d0b03c48e9879ef2ea6/File/setutuzufurufolun.pdfIn PDF document text
    • http://nano-vip.com/ckfinder/userfiles/files/lafabazukunusobujivawadiv.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/9595170403.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdfadb23a38---22737771576.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/e5afcbb4abb7628790acad00ba2b31b6/35144800623.pdfIn PDF document text
    • https://activepymes.com/pub/file/zekedalodejokifopix.pdfIn PDF document text
    • https://brs.jo/userfiles/files/92589653253.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160be7bdb4e0af---18231984376.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=fromm+p328+manualPDF 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_off0000b8dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8DD 16196 bytes
SHA-256: 486539b9e538255e1705b98b7f6c7ca30a9d02179cc21110ace890dc242dcc4c
font_01_sfnt_off0000e295.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE295 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000faac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAAC 10500 bytes
SHA-256: 353ec246dfdc54c93dbe300f4c27b957a157b4c7e7f2ca90b966e8cab541e258