Malicious PDF — malware analysis report

Static analysis result for SHA-256 811c932b6926fbdf…

MALICIOUS

PDF

79.6 KB Created: 2021-06-17 20:02:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b759ac9bf9ae8fc4a5a9ebb67f868e28 SHA-1: ba956cef8888b8572708f3cd758f1fc466ec63e4 SHA-256: 811c932b6926fbdfea40804b8542ec5f27c56ea6fe79d4a566fa3f460413b51f
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains heuristics indicating it's a link farm on compromised WordPress sites, likely designed for social engineering. The 'SE_CLICKFIX' heuristic suggests the document instructs users to execute commands, a common tactic for bypassing macro restrictions and delivering malware. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to download and execute a second-stage payload via the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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://philabc.ru/uplcv?utm_term=windows+10+taskbar+transparent
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/81k236dhiuuefl9idgqjbtk852/fesudesomikuponibuwofevu.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/3o6e8blsrsba277cfts7l358tj/rizunuselobokunafo.pdf
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/54e9a682ffda4d7fa71762cbdb000a03/58901576403.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712a797287f---nekedatazukiwinavuvawujo.pdf
    • http://mikailang.net/userfiles/file/20210507143125_1593142975.pdf
    • http://holidayinntorino.com/userfiles/files/44039959096.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/74579ecea9d966045684fd407768af58/pujazaxaxalet.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/i08b9d9ncerpe22iuf3c3hcijr/19612783421.pdf
    • http://macautemple.com/userfiles/file/90530286017.pdf
    • http://frezerovka.by/images/fxeditor/file/51505692769.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee2af800ee---kafofojolobuxanexozuvitu.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce6ac1d0db---48210813853.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/503671411cceb576039405a8754ee5d4/dabixaluwoniropipujazeti.pdf
    • http://suamayin.biz/userfiles/file/23598696933.pdf
    • https://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/96pmdjdobiv8mb4bqh6afoao63/sovunejorijepakatasune.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2b45b4149---41668557926.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4a5.bin
84a5c9f8a3700e1dd389fa84bc5210ecd5fb83d5cff5354a7ef8656966b1c3ba
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A5 5424 bytes
font_01_sfnt_off0001073f.bin
866268177a93658866d9ba2b278b4f74bf9751e120a0043a519952d4bad617e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1073F 12396 bytes