Malicious PDF — malware analysis report

Static analysis result for SHA-256 99c8aad3baa9ad79…

MALICIOUS

PDF

89.5 KB Created: 2021-03-25 02:52:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1dfa509a5f1c12c3443aa1fc35690cc9 SHA-1: d48504a9413ee68a075d952d4ab01fbc95f38637 SHA-256: 99c8aad3baa9ad7974246ca9c5a5e7aea3ed78c67d3be66fe748315be70986f0
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a significant number of external links, identified as a link farm, with many pointing to disposable hosting. The presence of the 'utm_term' parameter in one of the URLs suggests an attempt to track user engagement, common in phishing or SEO spam campaigns. While no scripts were explicitly extracted, the heuristic 'PDF_SEO_LINK_FARM' and the ClamAV detection indicate malicious intent, likely to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://resalured.ru/123?utm_term=hungry+shark+evolution+mod+apk+android+1 PDF link annotation
    • https://cdn.sqhk.co/werutojij/fkgjijh/wavir.pdfIn PDF document text
    • https://mexejafulid.weebly.com/uploads/1/3/4/8/134880369/dapezofikalesow_lelutafutexiruw_musomaji_xamafinokojo.pdfIn PDF document text
    • http://shimano-stradic.ru/dell_b1160_toner_price_in_sri_lanka3avq0.pdfIn PDF document text
    • http://wrinklestiltskin.com/20902189344d769.pdfIn PDF document text
    • http://artelamp.store/333164082665okzu.pdfIn PDF document text
    • https://feruzizujuvete.weebly.com/uploads/1/3/0/7/130775768/zixedozi.pdfIn PDF document text
    • http://stnold.com/what_is_the_best_powershot_camera4qwos.pdfIn PDF document text
    • http://bumaga.bz/novecento_baricco_englishyqhkj.pdfIn PDF document text
    • https://lowinegegin.weebly.com/uploads/1/3/1/1/131164077/6112868.pdfIn PDF document text
    • https://nanupubixo.weebly.com/uploads/1/3/0/9/130969545/zokovozama.pdfIn PDF document text
    • https://cdn.sqhk.co/kupujape/eidYjie/25138730899.pdfIn PDF document text
    • https://cdn.sqhk.co/kixowijeka/fKkzghg/pimesesulem.pdfIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb89c684-bb9d-4153-b40d-3047901466ec/98357838904.pdfIn PDF document text
    • https://6ba8113a-99dc-4618-97bf-d7180f10ff72.filesusr.com/ugd/b6edda_7c5079e6ec2e462c8009847fda230897.pdf?index=trueIn PDF document text
    • https://ba30dffa-51fe-4caa-9472-6f142403a9bb.filesusr.com/ugd/c2007e_b15a9fd0d5c4460fbf8d3de6eca88927.pdf?index=trueIn PDF document text
    • https://4a0f17ac-6ce6-4c05-9546-25c48d39d9f7.filesusr.com/ugd/cd79e3_e95d38bda4164ebb9b50f35a45d56bb0.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/08e1b6e9-f875-4437-b8cb-a8503b4f29c1/wheel_in_the_middle_of_a_wheel_scripture.pdfIn PDF document text
    • https://044ec7df-721b-4788-b209-87474a3fcb06.filesusr.com/ugd/60ffa2_115d508e09ac466ba273eb6427bfe37a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b778c560-a2be-41da-be54-42336ed4d843/what_is_100_day_plan.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://www.gnu.org/licenses/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00010571.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x10571 16808 bytes
SHA-256: b532153e007d561b1cc967cd8aa609ed4a37d9b3b72e4060b75e2a4404e3c0ac
font_00_sfnt_off0000f278.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF278 5612 bytes
SHA-256: c6739b978e94722d9dd460f85844b9b7feb12e1d2c1e5aa3cb07c5b76009e13c
font_02_sfnt_off00013418.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13418 10644 bytes
SHA-256: 20633ddd7730745064eddcf7ba36f8ebd648a44c3632222ba8cfba7122bcc54b