Malicious PDF — malware analysis report

Static analysis result for SHA-256 50d7c623c73a5679…

MALICIOUS

PDF

85.6 KB Created: 2021-06-28 12:20:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 41f8272148c48a9397d9a47fa0032e6f SHA-1: d803aa2ae67af9dbdca8c42a0e25909244e47ff6 SHA-256: 50d7c623c73a5679a9d28a983f790298e4a0ba5db63de013594be6c2c911f9ff
176 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised websites, a common tactic for distributing malware or conducting phishing. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of numerous unknown URLs strongly suggest this malicious intent. ClamAV detection further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/200d7b3442c3d819f7f189a46880c685/kivokufesir.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160c42a851b44d---16838515920.pdf
    • http://palenice.net/obrazky_clanky/file/lipebatusi.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b2611757ee5---fotikor.pdf
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/da53f67fb92a93606e49c0d05a1e06b4/gipepem.pdf
    • https://cvsc.co/userfiles/file/zipoxak.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/314f526f9f2e33c60fd4f62919ad0906/50683255852.pdf
    • https://aimhc.com/userfiles/file/33537796731.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/a2006bc5de739596acffbac410dfddc4/wusivanewal.pdf
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a23cda8577d---78301230423.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608f011aad33d---kebaxemifujiviwifujaw.pdf
    • https://bilegt.mn/userfiles/files/84136283426.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c21a381685---2854886235.pdf
    • http://afslab.asia/upload/files/57232162391.pdf
    • http://incucinaconalberta.com/userfiles/files/84192175909.pdf
    • http://kayamedbursa.com/userfiles/file/gasekabutemadivajufer.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/21f0f3b8c0a779c5506d86ec0c5a8270/35645417711.pdf
    • http://skupka54.ru/upload/m/66158686759.pdf
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/9bcfcjr2ph7ec8qj54elg49jb0/funona.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/ikk3333630akeeng4t9bppnf90/19351176243.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607965bd3d6dd---78181647640.pdf
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/uunbsu8npsp58ebeped0eioc00/67786739384.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd6a87fcf0---80769577653.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+get+your+chlorine+level+down
    • 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_off0000ee97.bin
2a8d4c3eee47a6788adbc0bcbf2bf5bf1f8a948cc7bd64bc8e7e062f7ba89d0c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE97 16396 bytes
font_01_sfnt_off00011904.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11904 16792 bytes
font_02_sfnt_off0001311b.bin
f91964d58929766967e49c56b91d5a494625da44347c2adee1607cfe5eec9b86
pdf-font-stream PDF embedded font (sfnt) at offset 0x1311B 10676 bytes