Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d28f98fe85f32f2…

MALICIOUS

PDF

80.9 KB Created: 2021-09-16 11:04:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b3a37ad29cdf4ef39accbe6e19199b26 SHA-1: 6d7066545b634df0f4f1d9a664a039b0944e99c4 SHA-256: 1d28f98fe85f32f28563be0b6555917bf7fb680beb004b3894a9b1826cbe1b00
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external URLs, many of which point to compromised WordPress upload directories or disposable hosting, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent. The presence of embedded links and the nature of the URLs suggest the document is designed to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://synerhu.ru/uplcv?utm_term=zipped+apps+download+apk
    • http://pretaporter-pegah.com/userfiles/file/87751624739.pdf
    • https://epagneuls-bretons.fr/caningest/images/file/tasuj.pdf
    • http://tecs4.com/intranet/ckfinder/userfiles/files/pazefu.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16135fc96c2129---gufufis.pdf
    • http://papaicountrylodge-longstay.com/user_img/files/bivukuzuwon.pdf
    • https://dehayemek.net/upload/ckfinder/files/78286972602.pdf
    • https://llbyggodesign.se/UserFiles/files/14372264195.pdf
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/25728472757.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136bf758b6dc---kejewidoruxebapujejo.pdf
    • http://exosportsante.fr/ckfinder/userfiles/files/mimajixaloz.pdf
    • http://alpinist.store/sribati/editor/uploadfiles/gigogukejikajodo.pdf
    • https://cs168.tw/upfiles/editor/files/77494923472.pdf
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/febikikevorejufexekixetas.pdf
    • https://alyosserspneed.com/userfiles/files/35156011269.pdf
    • http://opgzvh.hr/upload/file/13331603426.pdf
    • https://fcksa.com/ckfinder/userfiles/files/ronugipupofutuxiv.pdf
    • https://www.abrasco.org.br/ckfinder/userfiles/files/99808255806.pdf
    • https://funbugs.ie/userfiles/file/49451080547.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613562a18f76a---1983930533.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16141d08978642---87923349656.pdf
    • https://mimpishio2bet.net/contents/files/jijirotobanikuji.pdf
    • https://tauthuy.vn/upload/files/ninog.pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/1b529b5022c342ec8c1c5789a7317986/4946096752.pdf
    • https://corcreation.twbiz.me/data/fckeditor/files/20210914_014642.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_off0000d94c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD94C 16792 bytes
font_01_sfnt_off0000f163.bin
104259db2756215afb7bacf4fade1ab1a44399ae535ba6379cd1090eb60788f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF163 10328 bytes
font_02_sfnt_off000108d8.bin
fa71c33095754f00d488de540589ad6ff56445fd4c3776b99fd2b3cba38feb57
pdf-font-stream PDF embedded font (sfnt) at offset 0x108D8 17584 bytes