Malicious PDF — malware analysis report

Static analysis result for SHA-256 1fc3705745a1ed74…

MALICIOUS

PDF

95.4 KB Created: 2021-07-26 07:11:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9ac61cb3f9f152fea9ea3569f3a576a3 SHA-1: 4c459993b563f34989ccb9995ce5353cfa790afb SHA-256: 1fc3705745a1ed74321f8da2e7f5e8d329b4b61e8f110db7370420ff63b21b9d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. Heuristics indicate these links are intended to direct users to external, potentially malicious content. ClamAV and ML classifiers confirm the malicious nature of the PDF, likely due to its role in phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160814b47ca79f---tonapixo.pdf
    • http://landmanenterprises.com/clients/6/66/660ad4be7ac834282af30b44844c6003/File/97720483495.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608646058089c---35321015948.pdf
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/7942e11800b69214225e08ae7c39b3ce/4384942227.pdf
    • http://aftckwt.com/uploads/file/kurodumebusakezutajex.pdf
    • http://100gastro.cz/soubory/files/71593866863.pdf
    • http://laros.cz/UserFiles/file/gutevudi.pdf
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e9700974db---14543571870.pdf
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/3d1ace39cf6c0db06c81821950f0fec9/56934004772.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bc930b75f8a---wamujixafan.pdf
    • https://dm288.rs/slicice/file/33465495376.pdf
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abe17130bac---18003378768.pdf
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e7226f3a35d---timegerutel.pdf
    • http://lysfyyy.com/upload/files/89640201813.pdf
    • http://cephedanismani.com/images/pages/file/34355793697.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/fsggdr7l95feataj8l9daevjv2/57583856849.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bf7eb46f36c---79302676479.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/96bf2965033fa51072144ef0c721af50/sawenewuwutumerebuzaxamax.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/16086d5feacb44---fetisikiduvolabu.pdf
    • http://narcisse.sk/editor_uploads/files/rewixijubegub.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/e3110243f7edd970664e12e738b5dddc/61670818431.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ccc5d7f7a---bedom.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f305bbc1c9---3894193966.pdf
    • http://manavpublicschool.org/manav/userfiles/file/didufofovuxupapilizupi.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a84d09b56---56438697367.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=properties+of+equality+and+congruence+worksheet+answers+math+giraffe
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f60b.bin
aca4e313f566f2aa5a9e91c7a04fd2b9e63989901d5866a8d1123fabeaa9de0c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF60B 11608 bytes
font_01_sfnt_off00011102.bin
a425b10d01a7c3df9cf2d6996ed20b8a839e8e8e8d487d1caaa5fa0f6f480f2b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11102 18128 bytes
font_02_sfnt_off00014076.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14076 16792 bytes
font_03_sfnt_off00015887.bin
450eea5fc67953cc3bdc764260aa6f1739571c17331c9588074966c3dbef4c6c
pdf-font-stream PDF embedded font (sfnt) at offset 0x15887 16088 bytes