Malicious PDF — malware analysis report

Static analysis result for SHA-256 016e83fc47100037…

MALICIOUS

PDF

92.9 KB Created: 2021-05-31 08:00:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 39e59e28e79b28348dca35cd370157f4 SHA-1: 6856b295841f283288da7a27615434890e6787f7 SHA-256: 016e83fc47100037dab08e540f5864799b244b6ecd2b03e35c40d078e5a16f8f
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to manipulate search engine results or distribute further malicious content. The presence of multiple external URIs and the overall structure strongly suggest a phishing or SEO spam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/983c34c074e9e71f0f6a343460fb66c8/fogamutokamejate.pdf In PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/1608f016390564---83047007333.pdfIn PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/46d7499cf768ce59550489a1b19b2580/gowogumaboxadaturijuji.pdfIn PDF document text
    • http://eltonltd.ru/sites/default/files/uploads/letadekososabegekusewiwi.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/3ugvujqaknnfgerdsvno1jpn40/gawidaru.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/c2806c15919ffbe75a56383dfd079ff0/53400323263.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b297f01b54---97122983338.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/414b3d6a14b0b510b6355e361bc54504/21716627626.pdfIn PDF document text
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/0d209qkf3rueb8q6hvet0eua7l/xuxokuzoraro.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a698c43b757---bokeraru.pdfIn PDF document text
    • https://mymango.ru/wp-content/plugins/super-forms/uploads/php/files/7f6e740f84ee303b938e93df1d8e76d3/romizanazob.pdfIn PDF document text
    • http://eurogeographyjournal.eu/admin/fckfiles/file/61448645107.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=idioms+and+phrases+exercises+with+answers+pdfPDF 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010775.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10775 5460 bytes
SHA-256: 87f49be834124b231211596441be0cddba2ab20cec7cffc58e55ba9843ceb4d3
font_01_sfnt_off000119f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119F4 12760 bytes
SHA-256: 9e0a6d575d581d54a74a34e82b448589d3136b193229b457c1d56f0dab49325b
font_02_sfnt_off00014539.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14539 16204 bytes
SHA-256: 541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501
font_03_sfnt_off00015a65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A65 6064 bytes
SHA-256: b2bdf66ca980107e448388a8139f23d04f8038f6fc2436739650046121c4fb3d