Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fed71438745ae66…

MALICIOUS

PDF

155.5 KB Created: 2021-07-05 18:01:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3332bef4dd9c7fd6a92186241d039e4f SHA-1: 09ebef8ef09b6017dcf607e6a3031e09486eb20a SHA-256: 7fed71438745ae660eef2be49b8302e3827a84095c3ed2cbe7dcc6444e6222e4
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous distinct hosts, many of which are compromised WordPress installations or utilize disposable hosting. The embedded URLs suggest a phishing or malware distribution scheme, leveraging these compromised sites to host or redirect to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/hvtci5gn0pt9tug94riegr0t53/18091799911.pdf
    • http://www.zywawiara.pl/pliki/15677988916.pdf
    • https://mbzl-pro.xyz/web/img/podborky/files/rixawujiwewurik.pdf
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/ntjigokgg9p6m1c4siv50rq8et/38365965107.pdf
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/eef3a089546257f1c2d57b8fb05a2800/bafivujajubo.pdf
    • https://equantumconsulting.com/files/files/44402356393.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff2ec75b4f---64001445260.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/ffc37f4d1f31e1b370f3d1b23522298b/86340688444.pdf
    • https://299-45.com/CKEdit/upload/files/nukugosimuf.pdf
    • https://vsetinrally.cz/userfiles/file/gexunalojukavo.pdf
    • http://bobas24.pl/Upload/file/mulekagibakaniv.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/ce49a6f30c7d534b7880f6a54a33f10b/sodewug.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/d054bd333d2bc7cc9711da822247605a/81296100733.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0483763d8---35006163092.pdf
    • http://kutscher-customs.de/gfx/userfiles/files/sedupupafuwedumevirebudor.pdf
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/1608b4085859cc---13200443616.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/8347fb18mc60m1qjami44n8le2/melut.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/nb2ec53dlvcd9pb057qlqj812h/96879089781.pdf
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/5c2c059dc80b9c371e06fd19f29ceac2/poreguwifutud.pdf
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c94e4bb85f8---pitavurorox.pdf
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160a590a3b5041---89498670330.pdf
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/e9105ea5cfd68c81d300d9ec9e070102/9873446966.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=simplifying+equations+with+variables
    • 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_off0001fecd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1FECD 16792 bytes
font_01_sfnt_off000216df.bin
de876bb5936250a31dddaa36395a9f657e89b158e17ce7d51a6945470e5fbd05
pdf-font-stream PDF embedded font (sfnt) at offset 0x216DF 17944 bytes
font_02_sfnt_off000245dc.bin
968eb55327663b58c3772c261de05cf77e6172ec478ce115fa71670146783521
pdf-font-stream PDF embedded font (sfnt) at offset 0x245DC 11532 bytes