Malicious PDF — malware analysis report

Static analysis result for SHA-256 55156bcee8ed7ab7…

MALICIOUS

PDF

76.4 KB Created: 2021-06-28 03:50:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 1ad0594e658d81e8fb1b1e86f79fc89d SHA-1: 3b14a118bca31e4244bba298b1121123fcee8ad1 SHA-256: 55156bcee8ed7ab766bee2ae26dd3ea9c2170ac65be440c8c74f55a40fa62de8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous distinct hosts, many of which are associated with compromised WordPress uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites. No scripts were extracted, and the document body was unreadable, but the heuristic findings clearly point to a link-based attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://fkhd.cz/data/img/29351917210.pdf In PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a353ee50a5---noxedufixikajosi.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/d74a95c95e75f0cb8d2acd71d9d34de9/xoguwasugonizatimomoli.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/bc84efa1c7ebb2cbe07b874be6ea11d9/57668243573.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd74d50e1e---geralofenazenodidobonoliv.pdfIn PDF document text
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/koroxuros.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/74pmhgs0k5b970pl8ijkm5eivp/wikomijilaxiluvevuja.pdfIn PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/73518998787.pdfIn PDF document text
    • http://amazingindiaphotos.com/amazingindiaphotos//upload/fckimage/file/nebupifozofak.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075f340442d2---59020923555.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/vowidufufo.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c418350bd41---82703052983.pdfIn PDF document text
    • https://lotteppta.com/beta/assets/file/puxigavapeza.pdfIn PDF document text
    • http://reicar.dk/userfiles/file/nofebu.pdfIn PDF document text
    • http://csc0311.com/userfiles/file/20210624053248_a98608.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1607285326cb19---najez.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/a5ea8fd1f33b26155d42f776118021a1/94167598863.pdfIn PDF document text
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/d4e520b66dd17faf422d4b2df3124128/sifibosu.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/3a7abb0f69b2c5202f4d60211bde4811/52354785225.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160765754a335e---33923697599.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b54e37158d---bebawukexajolukav.pdfIn PDF document text
    • http://www.celso.org/download/kuvakowexesuwuwatuzabiv.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/4a7cc693fcc1facc5e98a529d5dbb4c5/dabuwedibo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=the+speed+time+graph+of+a+particle+moving+along+a+fixedPDF link annotation
    • 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_off0000c745.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC745 11196 bytes
SHA-256: b386918ef52015b4a1292ab9a6883fea25346f941f401bcfb83d11e075d3b17b
font_01_sfnt_off0000e122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE122 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f934.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF934 16492 bytes
SHA-256: 0777ce3f5f957ddb71a69a0bd17a7cde7e22988efc18c04e2acaaa67bd136248