Malicious PDF — malware analysis report

Static analysis result for SHA-256 3dbeb6d369b47364…

MALICIOUS

PDF

82.2 KB Created: 2021-09-20 17:38:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c2711c02c6d96655ae992c675b89e664 SHA-1: e7eca8b5b3aab1621be664d3cb57e659fa3e9793 SHA-256: 3dbeb6d369b473644d71e05d6604642e30bfaccb10fc4b3dfe5a559f028b511f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by a machine learning classifier and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs that point to compromised CMS uploads and disposable hosting, often with UTM parameters suggesting a lure for downloading software like WhatsApp. The presence of multiple external URIs and a link farm structure indicates an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://allytemp.ru/uplcv?utm_term=whatsapp+apk+file+free+download+for+pc+windows+7
    • http://writtenmail.com/upload_images/file/30501873329.pdf
    • http://af.ssla.ru/images/fornews/files/konodigibu.pdf
    • http://euro520.net/userfiles/file/16317885111371652299.pdf
    • http://toonesk.com/upload/7960220052.pdf
    • https://tannhatviet.vn/upload/files/vikabezoboxedebisu.pdf
    • http://sinosteelcode.com/filespath/files/20210906173822.pdf
    • http://vlajamo.cz/images/file/damumuduribazarigezig.pdf
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/16146f433cb7ed---28355778349.pdf
    • http://fukaofoods.tw/uploads/files/202109171403382559.pdf
    • https://dynasty888.com/image/files/20210919_002916.pdf
    • http://debten.net/UserFiles/File/dunifalivuda.pdf
    • http://aedelsur.com/contenido/files/56900088273.pdf
    • https://wupaojichangjia.com/d/files/67307027654.pdf
    • https://www.antoniopopolizio.it/ckfinder/userfiles/files/61937484920.pdf
    • http://conganbacgiang.vn/app/webroot/uploads/files/bubenafakumumuvepegajar.pdf
    • http://asavn.vn/uploads/userfiles/files/29532397468.pdf
    • http://swhwsolution.it/ckeditor-ckfinder-integration/uploads/files/22583538262.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16142b827691e3---79599860555.pdf
    • http://otworz-biuro-podrozy.pl/userfiles/file/48371023055.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161467d7992250---wonabadadewizamovo.pdf
    • http://kahasat.cz/data/file/wuposepefelokatogakekod.pdf
    • http://neoclassicalmansions.com/uplds/file/gegufodudikusubojebix.pdf
    • http://atletika-pardubice.cz/files/file/10554646101.pdf
    • https://wisestudentz.com/userfiles/file/movidowavi.pdf
    • 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_off0000d8f3.bin
a5d2b6199ae67aa03bddb998de1922cde2fe623164070c6ce8a5790d1c48bd96
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F3 18468 bytes
font_01_sfnt_off0001091d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1091D 16792 bytes
font_02_sfnt_off00012134.bin
255b81d301b3f2f25604167d40a11566bfff1a5e6d0a1b672313f5303271a4b6
pdf-font-stream PDF embedded font (sfnt) at offset 0x12134 10940 bytes