Malicious PDF — malware analysis report

Static analysis result for SHA-256 325c84077bc4793b…

MALICIOUS

PDF

98.1 KB Created: 2021-09-04 10:11:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a4271cd95efd743c02001d7388d1c9ef SHA-1: 685c1abcb5d6d5e82bb4042e130eaf8cec3b42df SHA-256: 325c84077bc4793b8556c45399ea94bec18347874e58b5c8f7c2e4f0f57ea309
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to PDF files hosted on what appear to be compromised WordPress sites. This suggests the document is being used as a link farm, potentially for SEO poisoning or to distribute further malicious content. The ML classifier strongly indicates maliciousness, and the structure aligns with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • 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://medvor.ru/uplcv?utm_term=simulation+modeling+and+analysis+pdf+descargar PDF link annotation
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/16084a18279806---3343474904.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-5-5/20210505155902448730.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/25fae2a07022173aa6cfdb66559a741a/jupikagir.pdfIn PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/jamadi.pdfIn PDF document text
    • https://hockeymro.ca/docs/file/63037563410.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/eb340f3be5414c774d090fd51e377ba5/78659217602.pdfIn PDF document text
    • https://citytrafik.nu/images/file/21744311113.pdfIn PDF document text
    • https://thinkhigh-tech.com/d/files/deporikejuroja.pdfIn PDF document text
    • http://thehedgerowchronicles.com/ckfinder/userfiles/files/35639734914.pdfIn PDF document text
    • https://samowar.ch/upload/file/21706879339.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/ritufu.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/turenodejosaxese.pdfIn PDF document text
    • http://xn--e42bt3l.net/upfile/files/90797704494.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1621281527.pdfIn PDF document text
    • http://dsm-trhs68.com/clients/8/81/818e764d3414495a915a5f66638dc9bf/File/suxozegisego.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607814d54369e---73639035001.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082710218a09---15773128715.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/vv7i9nk1qo4ol35gpelmq7u10b/mirupowuwabad.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca95a9475bb---57733097974.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/t80erie1unk1sthnr69df89ov7/40646566236.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f634d385a67---naredu.pdfIn PDF document text
    • http://archgeo-leszno.pl/uploads/userfiles/files/melos.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f3189abfcc9---6326483890.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000116d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012ee8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EE8 11252 bytes
SHA-256: 7ba1faae6f890b90240bfe4fd0ab5a4593b847c4a429d537b1722f073eb3f3de
font_02_sfnt_off00014912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14912 18748 bytes
SHA-256: 66b8110861a2db53208735d764c9845a20d3972fe8a6682686fb1a5d16d4cf7f