Malicious PDF — malware analysis report

Static analysis result for SHA-256 a19a8a833516a94c…

MALICIOUS

PDF

69.7 KB Created: 2021-09-24 22:11:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fa32e5e283e1c895c356f0ac5fb765d7 SHA-1: e1da603183f11e6b1a5eff5657d65f2fa1073bae SHA-256: a19a8a833516a94c4c986b7be2b3236dac81d3fa67a32fa3e4cc1a939b4d19df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics identified the document as a link farm, with many URLs pointing to compromised WordPress upload directories. The document body is heavily obfuscated and does not provide clear textual content, but the presence of numerous links to potentially compromised sites suggests a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0ed258bc1c3312efa8501169e8cc298d/tabobifobi.pdf In PDF document text
    • http://finalbrand.cz/upload/file/tomutuxeronulibelodepige.pdfIn PDF document text
    • http://winecellarkeeper.com/ckfinder/userfiles/files/1021893770.pdfIn PDF document text
    • http://slabowidzacy.smprzemysl.pl/ckfinder/userfiles/files/fokelivuvonipufoxore.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613c11e53e2d0---busomurumo.pdfIn PDF document text
    • http://tomekorea.com/userData/board/file/xonufodupodukeri.pdfIn PDF document text
    • https://etonbio.com/newsLetters/images/file/72437805467.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c111aaf95---ruvevavelifokufenasebo.pdfIn PDF document text
    • http://zensushidanapoint.com/uploads/files/84229530818.pdfIn PDF document text
    • https://ecohort.info/userfiles/files/bofixurojisadile.pdfIn PDF document text
    • https://dtd.com.pk/ckfinder/userfiles/files/sologepufatetipedopum.pdfIn PDF document text
    • http://rnralpha.cz/res/file/64086220014.pdfIn PDF document text
    • http://moneymaker-gold.de/files/55375535384.pdfIn PDF document text
    • http://bhavalaya.org/ckfinder/userfiles/files/15701791678.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/65189883184.pdfIn PDF document text
    • http://giaydantuongphongngudep.com/images/news/file/93011564454.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/vaporowunipibuw.pdfIn PDF document text
    • https://dimensioninteractive.com/WYSIWYGImage/file/fuponipavagajowaxu.pdfIn PDF document text
    • https://implant-drill.com/userfiles/file/17029326065.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-4/20210904173714585342.pdfIn PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/dafepijiwagixame.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/64478693140.pdfIn PDF document text
    • http://mhzsolutionz.com/userfiles/file/41400037378.pdfIn PDF document text
    • http://studiomalpocher.it/userfiles/files/taxenutodako.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=ets2+telemetry+skinsPDF 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_off0000b027.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB027 10296 bytes
SHA-256: 4c16d7c52cb01743dc17f438ceeb7a43c34b737da198b05d371b115e14210731
font_01_sfnt_off0000c753.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC753 16508 bytes
SHA-256: e48f75c346024e184dc03013cfbd49545f5d9b4bc61af17671d9179f4323c7f0
font_02_sfnt_off0000f182.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF182 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1