Malicious PDF — malware analysis report

Static analysis result for SHA-256 05e355390bd689b8…

MALICIOUS

PDF

79.3 KB Created: 2021-09-11 16:07:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1d6d92478979019036ff8bf7a466fd79 SHA-1: 6d5ca9111ad5ce6ade3f2788a9166e7692da4ab3 SHA-256: 05e355390bd689b8f9e8b1629822adc9a2c4905b59e877cf2d0a0710b41cf835
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic point towards an attack pattern focused on redirecting users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • 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.
  • 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://krisoc.ru/uplcv?utm_term=pcsx2+emulator+apk PDF link annotation
    • http://yuilchem.com/userData/board/file/52030496586.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/49830767888.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/52039378981.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/tivopuzu.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/1ulv90hbgoc8dtc4s82pvd4046/67869178588.pdfIn PDF document text
    • https://firsatpin.com/calisma2/files/uploads/27883494747.pdfIn PDF document text
    • https://megatekspb.ru/sites/default/files/uploads/64246950103.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210908004404.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6c6a215d1---33761445339.pdfIn PDF document text
    • https://byocamacho.com/ckfinder/userfiles/files/53186136168.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/2601659935.pdfIn PDF document text
    • http://hissekurban.com/resimler/files/masafifi.pdfIn PDF document text
    • https://giaynangchieucao.com/userfiles/file/89767255410.pdfIn PDF document text
    • https://www.meditech.cz/ckfinder/userfiles/files/gusidafuvozoze.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133d5b52b37b---vusaxajidutufeva.pdfIn PDF document text
    • http://paulgraphics.paulsfashion.in/files/zuwegizikuxakupezu.pdfIn PDF document text
    • http://gimhaejazz.com/fckeditor/userfiles/image/lafazaguxefijizowu.pdfIn PDF document text
    • http://hoaphathotel.com/luutru/files/36379938432.pdfIn PDF document text
    • http://aatmicscience.org/asuserfiles/file/vabavadizelajapigiwizuti.pdfIn PDF document text
    • http://thuephotocopytaihanoi.com/upload/files/tuledoraxuvusebaxazuxas.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_off0000d2aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eac1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC1 10752 bytes
SHA-256: 10ebda0543eefbff0a4e044b4774158f2f2995f4169fbd9b51269b18eea38a47
font_02_sfnt_off000103aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103AA 17252 bytes
SHA-256: d44b821be0acd71854057977966509c2fbde79fa28981f3a9f51997f5464f82b