Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3c0e7701a4d5836…

MALICIOUS

PDF

79.0 KB Created: 2021-09-11 23:45:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f4f78e3d280b7474eeb8321634aa031a SHA-1: b26f8cb1df807e810254d8e30c423b008b162b31 SHA-256: a3c0e7701a4d583614683cc992b55b62396d499cdf0ef54d4e68cb2c18eed24a
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farms points towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://inwebjor.ru/uplcv?utm_term=azar+mod+apk+2020 PDF link annotation
    • https://angkortaxiservice.com/userfiles/file/ribixarawawujoxurizor.pdfIn PDF document text
    • http://pmrs.ps/userfiles/file/98437298176.pdfIn PDF document text
    • http://fobas.cz/userfiles/file/goxazebilejimuwe.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131ce95822d2---628498218.pdfIn PDF document text
    • https://zoldlaptop.hu/ckfinder/userfiles/files/lisoranelimozugad.pdfIn PDF document text
    • http://ymmicro.com/files/files/jodilo.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20210905041921710208.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/44208875141.pdfIn PDF document text
    • http://gulfapex.com/uploads/file/46761562577.pdfIn PDF document text
    • http://baloneacessorios.com/_upload/file///67839818732.pdfIn PDF document text
    • https://www.creativetalentnetwork.com/ckfinder/userfiles/files/84320170084.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b91a91004---vibimumapox.pdfIn PDF document text
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/dedaxobagunexede.pdfIn PDF document text
    • http://auroraenergyproject.it/userfiles/files/57566000260.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/novavokegozedafo.pdfIn PDF document text
    • http://smolensk-bakaleya.ru/userfiles/file/denavolaxugikari.pdfIn PDF document text
    • http://djk-winkel.de/images/uploads/file/pinenuzetigunixoxig.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/42155361207.pdfIn PDF document text
    • https://mywayrtk.com/userfiles/file/69543747169.pdfIn PDF document text
    • https://sogelec-eng.com/files/ckfinder/files/31456155734.pdfIn PDF document text
    • http://s-privod.ru/userfiles/file/60159765923.pdfIn PDF document text
    • http://hamishehbaharcarpet.com/My_Project/Hamishe_bahar/ahar_img/files/rofolemajofigumojovo.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/lqduaeb5qmv17971a1c8gienk5/tugukaripavugifulo.pdfIn PDF document text
    • http://awarelaxcentrum.cz/user_files/file/taxig.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/88760165466.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/96643914237.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_off0000d0c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C7 10288 bytes
SHA-256: d79248fa1c7611849ab952ed0a7247e3bf276b39935b38c4285156d214261122
font_01_sfnt_off0000e7fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FB 17472 bytes
SHA-256: dd8b611c252272d3063cef68e553a1dec9e24492849ab250c3b65edb7b21f04e
font_02_sfnt_off00011515.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11515 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1