Malicious PDF — malware analysis report

Static analysis result for SHA-256 55bc16aedadf8ef1…

MALICIOUS

PDF

98.5 KB Created: 2021-06-27 07:54:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e56e559383653d49f433f1e76a562adb SHA-1: 303d91e2d36d134740ffd66f073bb51f4d77a121 SHA-256: 55bc16aedadf8ef11ee230f2d04970975d9aa1538e5874e3fa257c3d7ea929b3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to obscure the ultimate destination and potentially deliver a second-stage payload. The presence of these links and the overall structure indicate a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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 https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/e735f51bac92130365a73f6f14871124/kirifugalopotigoral.pdf
    • http://gopherandsquirrelcontrol.com/admin/images/file/45193822616.pdf
    • http://www.anclupnapoli.it/userfiles/file/nemumoreverobe.pdf
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608326351b665---koxujogexolarovekisowuti.pdf
    • http://easyreturn.store/userfiles/file/57505569186.pdf
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/ruwetupiva.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/577ac42c9fe00eba9b86f5239fcef7b5/junovakokatu.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16074167b241e0---42754823882.pdf
    • https://signika.pl/Upload/file/49641992920.pdf
    • http://amon-syotengai.com/userfiles/file/vowudunuvixinokutopusolo.pdf
    • http://canoeing.by/pics/files/26226474615.pdf
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/3d8c37f96bcbdceabcd9078862ec8d83/93151640551.pdf
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/5159757e538c006ef6a5284efb3a4d52/zoxuvoputa.pdf
    • http://aarogyamedico.com/userfiles/file/ruvezobodekedanu.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/23f2e938bf979ca4171d0425be2e8fba/vamituwunelorize.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/5ptbupkbj5s3hanrcofd0vtf3q/rebuxemiv.pdf
    • http://creative-format.com/upload/editor/files/gagukimazebafaxovewoke.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/6f84af9562d293223685581267b40e79/fufonejixaxuwiri.pdf
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/r1hpm8k6lkjhddj0igars1f9u1/51068773465.pdf
    • http://pytextiles.com/userfiles/file/salejuzazozexas.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6192aa126---27068595056.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3d638675a---95087311830.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/b15cfab898bf91a5c37c500bd1cd9955/84000431697.pdf
    • http://computerdoki.hu/user/file/gilafabosalukopifisin.pdf
    • https://dcoderesearch.com/uploads/65621980397.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=back+pain+right+side
    • 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_off00012070.bin
f0ddce52e9b0a7ce86d693ce8ad4f1b5868fa14dd2c563126423bce34459be00
pdf-font-stream PDF embedded font (sfnt) at offset 0x12070 10772 bytes
font_01_sfnt_off00013911.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13911 16792 bytes
font_02_sfnt_off00015123.bin
28439eab5ba7d6f6799d76b05430137deb29eb6fe9d1232198c94a2478c223e6
pdf-font-stream PDF embedded font (sfnt) at offset 0x15123 16884 bytes