Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7838aca4c6d5008…

MALICIOUS

PDF

86.2 KB Created: 2021-09-18 15:20:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fc8cdd681b558d9a88e3279f35ae7e5f SHA-1: f8ef27b84e706586c766398f804bde6cf8b0dfe6 SHA-256: b7838aca4c6d5008fcb2a17d2cc5ffe05a3f476ef0443ce97fd8eb8529a0c08b
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised WordPress sites and disposable hosting, indicating a link farm designed to distribute malicious files. The 'SE_CALLBACK_LURE' heuristic suggests the document's content is designed to trick users into calling a number for fraudulent purposes. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or a trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 http://optykglowacki.pl/obrazki/files/38688738528.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/3276822dfa3de17dcb121806dd583a7a/24951417469.pdf
    • https://hyosungulf.com/uploads/file/xadeniluz.pdf
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/161341b24bbce5---76354376908.pdf
    • https://samirkumarpaul.com/ckfinder/userfiles/files/jijegubij.pdf
    • https://eccdc.org/application/webroot/userfiles/file/zamadutasitasixelufewix.pdf
    • https://dichvuketoansg.com/luutru/files/xagupufupemogemuzajevure.pdf
    • https://novsport.com/content/File/rakexomedulawavaf.pdf
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210910140537.pdf
    • http://headrepublic.pl/images/files/38806385340.pdf
    • http://zeguvietnam.com/uploads/ckfinder/files/tapal.pdf
    • http://cherriestattoo.com/ckfinder/userfiles/files/49552195107.pdf
    • http://nt-module.ru/ckfinder/userfiles/files/tusagexapikosej.pdf
    • http://coinproject.com/userfiles/image/file/dezojek.pdf
    • http://world-housing.jp/ckfinder/userfiles/files/85300195730.pdf
    • https://led7.ru/file/55063940720.pdf
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/bofipoletusif.pdf
    • http://epicridesnepal.com/files/bodujomovagixagudiwibufoj.pdf
    • http://jmlukanich.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/16178921065.pdf
    • http://cgemfoco.com.br/ckfinder/userfiles/files/87216526241.pdf
    • https://rivieresoceanie.com/userfiles/file/51590901076.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3462d370b---dowixof.pdf
    • http://dakov.hu/_user/file/xalifibux.pdf
    • http://yugang360.com/upload_fck/file/2021-9-12/20210912102504388720.pdf
    • https://www.newhorizonscrisiscenter.org/ckfinder/userfiles/files/gelajuzevusokunijimiluka.pdf
    • http://byecook.com/ckupload/files/38381278901.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=puffin+browser+pro+apk+mod
    • 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_off0000e9d7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D7 16792 bytes
font_01_sfnt_off000101ee.bin
7c5c506b5437102f6673ce17eae96e9ebf5d29e453d180cb7a36c82513cfb2e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x101EE 10936 bytes
font_02_sfnt_off00011b16.bin
83c640d2acca9261d8481d71fe9276c28099e6cd162a3226ffdb8f10e52fa6a6
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B16 18428 bytes