Malicious PDF — malware analysis report

Static analysis result for SHA-256 91a3ab9ef50d5a8d…

MALICIOUS

PDF

94.6 KB Created: 2021-07-16 18:57:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 58881516af94e0409276a1d6a2057920 SHA-1: 0ebece15075e289e1ad3fe733a84f7afbc2ee5a0 SHA-256: 91a3ab9ef50d5a8de0e564a9113eec3235e2329b2bb13dc7cd1264b732382718
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution attempt. The embedded JavaScript likely facilitates the redirection or download of malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://loctra.net/userfiles/file/57740447784.pdf
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/a5nq0osfnup7vt8dldlemis8o8/ruvezu.pdf
    • http://dianacb.cz/userfiles/file/porupem.pdf
    • http://bigandtallking.com/userfiles/file/sepufasatis.pdf
    • https://pottoka.info/files/galeria/files/20134923160.pdf
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/4458a7216df4a56a3e7f0280648ace11/13012746922.pdf
    • http://fishtech.org/uploads/userfiles/file/file/xedebesilegirig.pdf
    • http://arserwood.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210520064003604009sgvz81.pdf
    • http://chnli.tw/CKEdit/upload/files/zixopowivawojiwikutasibu.pdf
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/60cee8d6d73cd18698f8baf5315a74dc/vudomed.pdf
    • https://isosklo.cz/uploads/7214917183.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/4mq2gm7b7i328bpevqs6regv36/dokagedijar.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/c7nv6hlk9qdt34m7jk2t2mk7ok/vojevusow.pdf
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/4buqvkj6el75u1fm0s8g9r1qti/lituzajakegipi.pdf
    • https://gyandeepjkss.org/userfiles/file/fedegoru.pdf
    • http://ghrnightinwhite.com/clients/7/72/721f26fb9237119891afe8d29dbdfc29/File/lizejiruji.pdf
    • http://personnelstrategies.net/userfiles/file/jazorugogipaxipotomopokod.pdf
    • http://thunderstar.cn/userfiles/file/20210501072855795793765.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/0741a8491fee185268cc5ec13d9881fe/6581114764.pdf
    • http://sattamatkapatti.com/userfiles/file/xivomapobuwotumoj.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/24446b52c19be9eaa6b497cce532da09/33089722156.pdf
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/3f97d7f43905de237856a4c0593fe035/54499148186.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/akmvmbfllt1btqic3idsrjm623/xowasulapisoviwetot.pdf
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/o33e8725ih2352ap4j1ic1k7pm/falosedisewa.pdf
    • http://aarogyamedico.com/userfiles/file/dazibepakavodaxog.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=brussel+sprout+appetizer+with+bacon
    • 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_off0000f6c5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C5 16792 bytes
font_01_sfnt_off00010ed7.bin
ca454eb05a08007e871bc2d1c49461b3603702e2407bf639d3cfa211fbaaf7f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10ED7 17432 bytes
font_02_sfnt_off00013c9b.bin
cfd9e39434432abadfa214e14d707642b0ba2262c01cdb137b3dac37ffbeac5e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C9B 10908 bytes
font_03_sfnt_off000155b9.bin
5dbfc0d67acdc70a0d4f078c02db6678a92e4d74825a5c144e16bfb972144fcf
pdf-font-stream PDF embedded font (sfnt) at offset 0x155B9 16696 bytes