וְהַשְּׁמֻעָה֙ בָּ֣אָה עַד־יוֹאָ֔ב כִּ֣י יוֹאָ֗ב נָטָה֙ אַחֲרֵ֣י אֲדֹנִיָּ֔ה וְאַחֲרֵ֥י אַבְשָׁל֖וֹם לֹ֣א נָטָ֑ה וַיָּ֤נָס יוֹאָב֙ אֶל־אֹ֣הֶל יְהוָ֔ה וַֽיַּחֲזֵ֖ק בְּקַרְנ֥וֹת הַמִּזְבֵּֽחַ׃
Das Gerücht [von diesen Ereignissen] kam an Joab — Joab hatte es mit Adonija gehalten, wenn auch nicht mit Awschalom — da floh Joab in das Zelt des Herrn und faßte die Hörner des Altars.
Rashi
And the report reached Yoav. The report of Dovid’s charge, that he had commanded to kill him, and he knew that Shlomo hated him.17That is why Yoav feared for his life. Alternatively, he heard of Adoniyahu’s death and of Evyosor’s banishment.—Radak
Rashi
For Yoav had sided with Adoniyah, but he had not sided with Avsholom. At the end of the matter; however, he did seek to turn after him, but he was fearful that trace of Dovid[’s might] was still present.