Malicious PDF — malware analysis report

Static analysis result for SHA-256 141b253e915fb7b2…

MALICIOUS

PDF

88.7 KB Created: 2021-08-10 18:29:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 231f9e7a54e1b4ae45536331b21bfb3b SHA-1: 4b828596f7f6b1cc99dd13a8f1d156521d92f3bb SHA-256: 141b253e915fb7b2d6e4332157798de9246af0605a1d792846c4bb08ce29bb6a
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, suggesting it is not intended for user interaction but rather as a container for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://trlgpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nonug.pdf
    • http://rauvuonsach.com/images/uploads/files/21875692138.pdf
    • http://fotostudiovaccari.it/userfiles/files/45766130121.pdf
    • https://geneolock.com/locktactyuma/userfiles/file/darokuramu.pdf
    • http://sysquare.com/UserFiles/files/saxapebafikodiferemedu.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/dosaxifobugebil.pdf
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/de1c24a800b7db3006843319aec17b27/11938133550.pdf
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/7svo695a5jkujs5qp91v32b23k/sapurufamevikikimun.pdf
    • https://aawyx.com/sites/default/imageuser/file/13126095984.pdf
    • http://uniquecharacters.com/upload/files/71416254294.pdf
    • https://privatecambodiatour.com/userfiles/file/supuxogatuwusegom.pdf
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/789572ca2ac119eeb015f42b4f338d03/77466122688.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610026a22d85a---judelapet.pdf
    • http://hydrem.ru/images/file/vivifegox.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c724dc6ef99---pepexirivedip.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5f9eaad0a5---96052794904.pdf
    • http://bvmnotarissen.nl/app/webroot/files/ckeditor_files/files/99550538126.pdf
    • https://tavio.ru/files/file/numafumetu.pdf
    • http://bertolinacare.it/file/zevura.pdf
    • http://vieclamquantri.net/upload/files/75625802673.pdf
    • http://lncxjzxxw.com/upload_fck/file/2021-5-22/20210522064509180807.pdf
    • https://apartmani-mestrovic-krk.hr/files/bebijivese.pdf
    • http://photou.cc//ckfinder/userfiles/files/33832534248.pdf
    • http://apartamentosalbatros.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b385b10cd44---80522743444.pdf
    • https://tideandtigers.com/ckfinder/userfiles/files/terivixalipobinen.pdf
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/27379251561.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=why+did+my+skullcandy+earbuds+stop+working
    • 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_off0000f520.bin
b57216bb939254710f25b96f2a4c0ae216ef947b6e797c646be1bb6d04c2e5b3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF520 17356 bytes
font_01_sfnt_off00012268.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12268 16792 bytes
font_02_sfnt_off00013a7f.bin
7587301d6e2a35110f410169c4a6412ac63ac7ee2238f4e6a1802059b9c06be3
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A7F 11484 bytes