Malicious PDF — malware analysis report

Static analysis result for SHA-256 08cdc4d420a5aec5…

MALICIOUS

PDF

87.3 KB Created: 2021-08-11 01:31:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a8e19bd9d255d4f806c875b854d8428a SHA-1: 8580de373804caae6f7010b8b2b2bedd8ced2398 SHA-256: 08cdc4d420a5aec532769d7dddb176eb5b8f8ddf5f078e1851d8a3634df32be2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm hosted on compromised or disposable infrastructure. The presence of these links suggests the document is designed to redirect users to potentially harmful websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://crysiq.ru/uplcv?utm_term=dihybrid+cross+practice+problems+answer+key PDF link annotation
    • http://amsasecretariat.fr/userfiles/file/56622054828.pdfIn PDF document text
    • https://atpl.aero/ckfinder/userfiles/files/54891877265.pdfIn PDF document text
    • http://atek-ent.com/upload/file/duzubifeganinij.pdfIn PDF document text
    • http://frigotechreina.com/userfiles/files/xidamazime.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/mfhibrft219ije3l9uh9flh67v/kisajuderoz.pdfIn PDF document text
    • http://robbinsfamilyhealthcare.com/clients/2/2c/2c787fa606fc56c3a3a24dfc5409695f/File/juwajubavu.pdfIn PDF document text
    • https://seikico.net/img-tym/files/jupupapi.pdfIn PDF document text
    • http://asfalon.com/__files/file/51073292851.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/ae5ff068f8574a648c1e35bb5abe8a4b/22495484163.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/narezatigamenude.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/8k1u62hpp67tn5p37019dt3bm2/jozozujeliminofu.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1609f6e421172e---49595805829.pdfIn PDF document text
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/20dc58bad20b38180549bb98c6addd9b/16953391107.pdfIn PDF document text
    • https://gizaviation.com/uploads/files/pozatupowede.pdfIn PDF document text
    • https://unserbiokorb.ch/userfiles/file/28902373221.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f697245a60---53639579186.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160909cfa767e0---fuzexevakupux.pdfIn PDF document text
    • http://sahrugs.com/userfiles/file/66784607831.pdfIn PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/1fdac98398a9013b115670e17dce2506/70915215158.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7666801c83---reduzetit.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/3d19797f15926291d98725446fd97ffe/28008190645.pdfIn PDF document text
    • https://officialbacknumber.com/editor_up/mojetenowunozawubod.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/b00920c89b2aab76080d8b562ad1bbbd/28465913401.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_off0000ef3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010751.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10751 11212 bytes
SHA-256: 94dcc6f97d43155f1538847534c088c8ae4be5eb6bb69734f2ae9f5f697a5844
font_02_sfnt_off00012134.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12134 17556 bytes
SHA-256: 2683b516f96b32633d0a9bef6b2c624a64b20256cc6a57210f69fa28b4cb1bda